Is it about the story or is it about the characters?

More of, it's a matter of perspective than it is of the work.
Character-driven works have existed since the ancient Greeks but they looked at it differently. While Plato was obsessed with how perfect Oedipus was in terms of plot, we know tend to look at Oedipus as perfect in terms of character. In a way, the narrative of Oedipus will not have happened if Oedipus was a different person. Same goes for all Shakespearean plays. 

More than the work itself, it's a matter of who is reading it, where, and when.

For instance, Solas and Anders are only great characters because of the intense lore buildup regarding elves, Templars, chantry.

If we didn't feel the weight of the forces in the chantry, they wouldn't have a basis for their passionate viewpoints and actions.

Kaidan is weak because his main unique feature is his biotic implant that causes migraines. Except instead of giving him some special mission in which HE resolves to do something about that, which is tied to unique ME lore, it's relegated to backstory.

Mordin Solus and Wrex are great characters because they actually want something. Something related deeply to what makes the ME universe special. Solus to atone for the Salarian solution, and to be a proud Salarian scientist. Wrex, to lead krogans into a more progressive future.

Dorian is weak. He wants to reform Tevinter, but we don't actually see him do anything to really reform Tevinter or engage the Venatori in a dedicated story arc. We've got some venatori mooks that spawn in certain places? I guess? He's got some eloquent, well-voice-acted dialogue options in the library....?

But does he perform major actions? No. He doesn't go up to disperse the krogans cure like Solus, giving up his life in a cut scene. He doesn't deceive you and blow up a chantry. He doesn't face off with the Arishok and go up the city ranks on his own like Aveline. He doesn't obsess over a mirror or go through staged trials like Grunt or blow up a childhood concentration camp.... etcetera.

Strong characters Do things. They have huge motivations, obsessions, sensitive points. They are ACTIVELY INVOLVED in the main plot or at least some intriguing subplot that demonstrates the lore - that gives you a representation of aspects of the fictional world and its factions.

They do shit. It remains to be seen if Andromeda characters will have such agency.

I think characters are always the most important thing. What does it matter if there is some dramatic death if you don't care about the character. Also Bioware games have always had the best characters

It's about Bioware's Social Justice League.

For Bioware games, I do care about both, but characters are more important to me.

The plot and characterisation have to complement one another like wine and cheese. If one is poor, the other will suffer.

Characters and story aren't two completely separate categories. Whether a work is plot-driven or character-driven, the two need to work hand-in-hand.

This is like "making a story" 101.

Id agree that its about both but probably a teensy bit more on the character side. Dragon Age has been more about the world (which is why you switch main character every game) whereas Mass Effect has traditionally been more about the characters IN the world. Either way I dont feel as though either one will be sacrificed for the other so its not really an issue.

It appears to me that ME:A is about the combat and story/Characters are taking a back seat in this one. From what they have shown, the writing is sub-par. I'm guessing the story will take more emphasis this time around. The characters all seem too lighthearted about everything. Like nobody is really worried about anything.

Which is why, I'm cool I guess, when Fabrice says it because he's a producer dude, so he actually gets to be misconstrued about it but Mac - a writer - says it as his creative direction for the team and that's when I worry. If you fail to understand the actual cogwheels of characters vs plot you're bound to make both of them kind of lame. If you make a plot solely around making your characters be in the right places to make it feel tied together but they aren't actually interesting as characters you fail, and similarly if you write a bunch of good characters that have no plot to tie their stories into a larger whole (like good stories do) you kinda fail too.

The good thing about video games in particular is that they're like a more entertaining and visual form of literature. They're more comparable to novels than books in the sense that they both take much more than 2.5 hours to see through and because games are often wannabe movies with their cutscenes and cinematic tropes, they get to have multiple movies in one game but if one was to fully utilize the media for storytelling they'd know it's better to make a video game like a full-length novel instead. A 1000 page novel is bound to also show multiple stories or multiple POVs, maybe time skips and whatnot. Gaming is usually tied to experiencing a story through a single protagonist whereas cutscenes and other stuff is used to pan the story across other POVs but if you're not careful you'll just end up making multiple different stories in a long game that don't relate enough to each other while that 1000 page novel usually has a point that ties into its overall message about the various POV shifts.

This is, to me, what BioWare has both done really well but also failed at. ME3 was actually an example of them making a good novel-esque narrative just like ME1. It's different stories and the cutscenes sometimes show us what other characters are doing simultaneously, but in the end the story (supposedly) comes together to make all the subplots add into the main plot. In Inquisition the rather big focus on companions didn't add this element in my opinion, and I think it's because, much like ME:A, the devs said "Let's start by writing the characters and figure out the plot" or something. A few do tie well into the main plot like Vivienne, Leliana and Cassandra being closely tied to the Divine Justinia subplot and the state of Orlais and theme of Faith while Solas also has an undercurrent of significant story-importance that is brilliantly handled, but Josephine, Blackwall, Varric, Iron Bull, Sera, Dorian, they're all just sort of there and their character arcs have nothing significantly to do with the particular plot of DA:I. They are small vignettes of something to characterize the setting of Thedas outside the confines of DA:I's narrative framework (Bull is the Qunari and Dorian is Teviner. Tevinter = DA4, not DA:I - at least he's foreshadowing), and unlike ME2 their individual, wildly different, stories don't share a common theme (in ME2, as hamfisted as it is, it's "loyalty" and "closure") because the DA:I narrative doesn't have an impressive finale that accounts for the preceding plot well enough. I'm slightly worried Andromeda's final mission will also make the focus on exploration and loyalty missions have less impact in hindsight.

Like, the best case scenario for Andromeda is that the citizen of the Arks, particularly your squad, will be an actual focus to the plot much like the crew in Babylon 5 or Battlestar Galactica, and similarly our new friends and enemies, the Angara and Kett (and Remnants) are all part of a bigger narrative that ties together too so it's not just a series of vignettes to merely do this and that because the setting allows it. Mac has said in the past that he loves Mass Effect for giving him the ability to tell whatever kind of story he wants to because of its setting. I just don't want that to mean that from story-beat to story-beat Andromeda will juggle between genre and focus all because the writers decided to give each character their own isolated themes and concepts.

When plot and characters combine to make for an excellent story, that whole narrative just jells, to the point that its considered a classic.

IE: KOTOR, Fallout 1, Plancescape Torment, System Shock 2, Arcanum...ect ect.

Or even in Books like Dune or Starship Troopers or LOTR. There's a reason they are classics and still sell fairly well today.

So I think both aspects are very important.

Plot story is very important, but if you have a story with tremendous characters than people will let the story slide if it's an average story. For me Mass Effect was never about the main plot. Which I thought was enjoyable in all three games, but none of them are really great stories on their own. Mass Effect is about the characters and side plots involving those characters. That's what draws me to Mass Effect, or any scifi in general, are the characters and the relationships/development they encounter throughout the story.