These are just a few features or moments I would like in ME3
1) Miranda Confrontation. We know that Cerberus no longer has Shepards back. Is Miranda still loyal to Cerberus or is she in line with Shepard? Before meeting Shep she was incredable loyal to the Illusive Man and what he stood for. Will her time on the Normandy SR2 be enough for her to change sides? What if it wasn't and you are forced to fight her? What if persuing a romance with her in ME2 would prevent the conflict from escilating? That would be interesting to see.
2) Non-squad Characters. I am pretty sure that Baily is going to be playing a larger role in ME3. Heck, he got a shot comic just to expand on his character. I wouldn't be surprised to see him in the role of a temp squad member, which I think there will be more of. Will he get full squad member status? Probably not. Cerberus seemed interested in recruiting him so maybe we will see him in their ranks.
I see two possable outcomes for Anderson that are likely to happen. Either he will be a full-time squad member or he is going to die. It will be a dramatic and heroic death, to be sure, but die none the less. If I had to guess it would happen at the end of the game so he may still be a squad member in the way that Ashley, Kaiden and Wrex were in ME1.
Kelly Chambers will be around if you romanced her. If you didn't you may bump into her assuming she survived the Collectors base.
Joker and Chakwas will make a reapearance but I am not sure what will happen with their roles. Are they going to be punished for their role in Cerberus? Perhaps, but I am pretty sure that Shepard would still want to take them along when he gets the hell out of dodge. I recall that they are the only two on the Normandy who are guarenteed to survive the entire suicide mission. Joker stays on the ship and Chakwas will always be freed from the pods. That makes me think that Chakwas will be getting a larger role in ME3.
Kahlee Sanders may make her appearance in the games for the first time. She has become very, VERY involved with anderson in the books. It would be hard not to at least mention her in the game. I wouldn't be surprised if she goes along with Shepard if Anderson isn't a full time squad member to be honest. Is she related to James Sanders? Maybe. While Sanders isn't an uncommon name in real life, in fiction you tend to shy away from having multiple characters with the same name to avoid confusion.
Udina will be around in his normal Udina role. I really think that we saw the most of him in ME1.
3) Who is still alive? Before the GI article I thought that Mordin may die between the games due to age. That is not the case, and thank goodness. Heart Mordin! Thane on the other hand... I am left wondering if his disease will finally take him down. I don't think it will happen off screen though. My guess, you go to visit him on his death bed. Wouldn't be surprised if his son is there as well. That may be a possable squad mate right there!
4) Will this be the end of Shepard? I know it is the end of his/her story but does that mean that Shepard will die at the end of the game? Maybe. I actually think they may pull a KOTOR like with Revan, where between the games he leaves known space. Exactly the same? Probably not, but I wouldn't be shocked to see him leave the galactic stage after the fight is over.
5) Ghost of Girlfriends past. I have heard it said that romances in the first two games may complicate things in ME3 for any prospective romance. I think the combination may be the biggest factor. Romance Ashley in ME 1 then Tali in ME 2 and I don't think there will be much trouble. Romance Ashley then Miranda or Jack and we could be looking at a different story. Those are three strong headed women who seem more than willing to get in a fight.
Honestly though, I don't see as many of the match-ups on the fem-shep side. Kaidan was too easy going to see an all out fight. Maybe if you romance Jacob in ME2 but not with Thane, Garus or Chambers. As for Liara, I don't see much of a chance that there will be conflict there as you can deal with that romance in LotSB. She will either already know or still be with you.
6) Heavy Weapon mods. I know the guns are getting a bunch of new toys and gizmos and I would like to see that on the Heavy weapons as well. I also wouldn't mind see the "disk-grenade" from ME1 return. I actually used them quite a bit. They were usefull if you knew how to throw them. Kind of a cross between a Gernade and C4 really.
7) While Shepard's away... What did the crew do while you were gone? I know Shep likes to take out squads but in ME2 you had 10 highly skilled soldiers who did nothing every mission. I loved the end mission just because of how useful everyone felt. There wasn't anyone who seemed like they weren't pulling their own, even if they weren't a speciallist. It would be good to have a mission or two like that in the regular game for ME3.
Well, that is all I can think of while I am sitting here. I will post more as they come to me!