I want all DLC obviously as well as the visual upgrades and bug fixes remasters usually get.
I also want these changes [some are realistic I think, others are just my excessive wishful thinking that I know not to expect to happen]:
1. outright removing the codex and journal of ME3 and replacing it with a codex and journal in ME3 that works like the ME1 and 2 versions.
2. allowing you to get any squadmate in any order you choose in ME2 instead of locking Legion, Tali, Samara, Thane, etc into the post-Horizon portion of the game. The only lock I want to see in ME2's dossiers is being forced to get Mordin fourth [not counting Zaeed and Kasumi] if you hadn't gotten him already.
3. make it to where the Journal in 2 and 3 imports all the content of the previous games' codexes that you found.
4. replacing the wall of text you unlock by using the trinket the Consort gives you in ME1 with a cutscene depicting what the text was telling the player.
5. take the maps from the MP DLC and make new N7 missions out of them for ME3's single player
6. have Anderson give you the apartment on the citadel earlier in the game [maybe after finishing Palaven] and thus having access to the Silversun strip sooner in order to have more time to enjoy the casino, arena, and arcade. Then, when you get to the point where you can start the Shore Leave mission, have the mission activate by looking at the email from Joker via your apartment's pc and walking yourself to where the sushi place is.
7. speed up the process of mining in ME2 by increasing the speed your cursor moves at.
8. add cutscenes showing your war assets at work throughout the last mission
9. replace the interactive dreams with cutscenes of the dreams that are skippable
10. have the Omega hub world from ME2 be accessable in ME3 after doing that Omega DLC mission and through that hub world gain access to 4 new sidequests where you help the merc group fight the reapers [of course, this means Aria will no longer be at the Citadel after getting back Omega]. One for Blood Pack, one for the Blue Suns, one for Eclipse, and one with the Talons.
11. fix ME2's Conrad Verner encounter so you can see the actual encounter with him should you take the all-paragon route with him in ME1.
12. Include a bonus disc with the physical copies of the remastered trilogy or a digital download of a Mass Effect application on whatever platform you buy the remaster on that includes a remastered Mass Effect Galaxy, a remastered Mass Effect Infiltrator, a Mass Effect 3 email program, and soundtracks {sorta like the Halo Channel is to the Master Chief Collection}. The remastered Mass Effect Galaxy and Infiltrator would have you play with the controller instead of an iPhone/Android phone screen and completing the games would unlock the in-game bonus for you current save file of ME2 or ME3. Then, the next time you do a ME2 playthrough, you'd need to beat Galaxy again to see that exclusive conversation, same with ME3 and Infiltrator.