The Ideal Party Size

9 to 12. I like a lot of companions to have more diversity and it benefits replays where maybe you don't recruit some or they leave or can die. I'm replaying ME1 (LE) and I am sad how quickly I finish talking to everyone.

I think the very infrequent banter could be partially to blame for the lack of connection to DAI companions. DA2 was wonderful in that regard - pretty much entering any area triggered banter and I think that added a lot to the experience.

The problem with DAI was that unlike DA2 and DAO it didn't trigger when you went to completely safe areas, like Val Royeaux, yet would suddenly start just after you had been attacked by a random encounter in the wilds. This was infuriating because I spent ages trudging around areas simply in the hope that companion banter would start and then had to choose between listening to them (because it kept on going) or concentrating on actually fighting. So I hope they revert to the old system for DA4, so if you want to enjoy listening to your companions, you can just take a stroll around a market place or within a village, where you are less likely to be attacked, and can listen to them without interruption.

I also preferred the system in DAO where I take a break between fighting for a brief chat without having to return to main camp, or even have a quick kiss with Alistair to show my relief that we had survived the latest nasty. It just felt more natural than having to trek around Haven or Skyhold every time I wanted a talk (or for a brief show of affection) and ignoring my companions for the entire time we were away from base (unless the aforementioned banter actually triggered at an appropriate time and I was included).

I'd say 9 is about the sweet spot

6-8.

If there was a 6-9 option I'd select that as it feels like 6 is minimum, and 9 is maximum. We need more than one member of each class so that if someone doesn't recruit a companion, kicks then out of the party, or just doesn't want to take them they have another option. (Hence at least 6) And of course you just need different types of people for the PC to hate, befriend, and/or romance. That's more ymmv.

7-8 seems to be a sweet spot based on previous games.

DAO might technically have 10 companions, but Dog is more of a partial companion. He serves the combat role but doesn't have the same level of dialogue as the others (or y'know character development - he's just a good boy). And you can only have 8 of the remaining 9 at a time because Loghain and Alistair are mutually exclusive.

Similarly you can also only have 8/9 of da2's companions because you can only have Bethany or Carver, not both. And then whichever one you do get won't stay with you for the 2nd and 3rd acts - leaving you with 7 for most of the main game. (Thankfully they brought them back for the dlcs)

DAI was The first to let us have all 9 at once. Plus npcs with major content in the shape of the advisers.

I'd be quite surprised if we got more than 9 companions in the next game( maybe less so if there are no advisors or some of them are temporary and/or mutually exclusive ala Bethany/Carver and loghain). And I'd be very surprised by anything less than 6.

But I wouldn't be surprised by anywhere in the 6-9 bracket. Though if it were 6 then I'd think the chances of there being adviser level content npcs were higher.

Personally I do like there being 3 of each class. Whether that comes in 9 we can recruit at the same time like DAI, or 9 total of which we can have 7-8 at the same time based on our choices like dao and da2, I don't mind much.

Not having the best BioWare character ever is the opposite of good.

I do agree with your reason for having so many though, as I have felt the same about many companions.

That is the thing i like the most of DAO, that you can lose your companions even when you romance them.

9-12 for me as well
it gives you more variation and re-playability especially if you somehow manage to miss out on some companions first time around
for example, in DAO it was quite easy to miss out on recruiting Leliana and Sten if you rushed through Lothering
similarly in DA2 it was easy to miss out on recruiting Fenris because the quest given for recruiting him is quite vague (as in 'recover my stolen goods which are lyrium'...it's vague and you only later learn Fenris' markings are made of lyrium)
Inquisition doesn't have that problem since all companions more or less are brought to your attention

I just hope we get more varied specializations like in DA2...

Went for 9 - 12 myself, a decent balance of classes & plenty of content for all & really focus on fleshing them out.

9 is the obvious answer for a maingame. 3 for a DLC and 6 for an Addon.
And 12 well that´s too much. Everything else like 8 well you get some class less.
3 companion for each of the 3 classes is perfect.

The real question should be does DA 4 really need Advisiors and trainers?

I want equal numbers across the classes so I have options for a balanced party, but the actual total number doesn't matter.

However, if we were to only get 3-4, I would expect to be able to max out all their skills and unlock all their specialisations, OR I would want respec-ing to be easy and cheap.