-More playable races, like the ME3 online.
-Keep the ME3 gameplay with the possibily to carry the M-Cain like in ME2. (It's a shame you can only use it one time in the 3 :'( ).
-More interaction with squad members. (Good idea with Garrus on the top of the Citadel in the 3 : what about others characters then ?)
-More exploration in open-world planets.
-A true role play like the first one with several decisions and more dialogs. (I know it wasn't very important to have to choose every reply in the first one, but in the 3rd one, you don't have anything to do... )
-A good scenario without fucking inconsistency all the time. (NO MORE DREAMS with kids, please. Shepard isn't like that :p ).
-Keep the "romance" : perfect in ME3 !
And the most important thing : keep the spirit of Mass Effect 1 that was charming, peacefull, mysterious, with the epicness of ME3, the OST of ME2, and awesome allies such as... Well, Garrus, who else ?
Je posterai ça sur son twitter : des objections ?