Most important part of MEA for you

Characters&Romance for me, though I'm looking forward to a great plot.

I guess that's what happens when you can only choose one thing on the poll, but for me, plot ain't shit if I don't care about the characters, and in a sprawling game where I can go off the beaten path for hours at a time, I'll need something to fill in the gaps. BioWare's plots have always been rather basic anyway, from DAO and ME1 onward. While that's no excuse to skimp on the story, characters are a big factor in making it more worthwhile. 

A cross between characters and game play

Its a toss up between plot and characters for me. I think in many ways the two go hand in hand and are related. Like you can have a rich plot full of detail, intrigue and twists n turns etc but if you dont have interesting characters to bring about that plot and make you care about what's happening in the first placs then it becomes meaningless. Likewise you can have the most interesting, awesome characters but without a great plot to put them into, a plot to actually make you invested in said characters etc then that is just as pointless as well. Although you have to factor in world building also... As fantastic world building can very much so make up for a shitty plot, and thus still allow for great characters to actually be great despite a lame plot. Even more so in an RPG like Mass Effect, where lets be honest its main plot was always B movie-ish crap, but the superb world building and the superb characters kinda elevated the trash plot or at the very least caused one not to notice/otherwise ignore the lacklustre winging it plot etc. But even more in an RPG where world building, plot and characters really are everything. Of course being a game, gameplay still matters hugely, having a great plot and characters but without the gameplay to back it up, it will detract from everything else to an extent. A game still needs to be fun for the plot and characters to actually matter and make you want to continue on. But with story focused games its not the gameplay alone that what makes you fall in love with the universe. You need the solid foundations of a plot and characters in place first. In a way all three are in a symbiotic relationship with each other.

Asari boobs.

Why are these not an option?

I'd say a little bit of everything myself but seeing as how this is a Mass Effect game, characters get the edge over everything else.

Gameplay mechanics are probably #2 because that's the other thing we're going to be doing for the vast majority of the game along with talking to the other characters.

As for the question, what makes this game for me, aside from plot since we can pretty much throw that out of the window, me thinks.

- The world, has to be intresting and meaningful, with lots of exploring, intresting places and good vistas.
- characters and relationships, have to be intresting and meaningful.  Also emotianal moments, even if the plot turns out to be generic.
- gameplay, the less clunkier aka ME1 it is, the better

He dumb as a brick.

Sovereign too btw.