Need help with deciding what class to play ME2/ME3

Hello Everyone!


I've been holding off starting ME2 for a week now because I can't for the life of me decide which classes I'm going to succeed my ME1 vanguard with.

My first playthrough of ME I played the entire trilogy as a Soldier and picked the Revenant on the collectors ship in ME2 (although I've been madly in love with the Mattock since ever).
This is now my 2nd playthrough and since it might be my last (although I do intend to start at least a 3rd one some years from now) I intend to experience as much of the gameplay as I can. 

I started this playthrough with ME1 as a Vanguard, with bonus specialisation Assault Rifles, and distributed my time between using shotguns, AR's, and pistols quite evenly. I enjoyed using all of them. In addition I was always an active user of biotic abilities such as throw and lift.

Now it must be said that whichever of the two options I do not pick below have a good chance of being used in a 3rd playthrough, although I'm not sure which decade that will be in if at all (life's busy, I'm a completionist and my steam library still has 20 untouched games in it).

Which classes should I succeed my female ME1 Vanguard with (romanced Liara)? (mild plot spoilers below)

If ME2 infiltrator + ME3 sentinel it will go something like this:
Reason I lost biotic abilities ME1->ME2 all of the sudden, well, after being rebuilt I guess they didn't had time to implant shepard yet with biotic amps because of rushing and all. Doesn't really explain why she ditched Shotguns and AR's for Snipers and SMG's though. She'll definitely pick the Widow at the collectors ship.
In ME3 during detention after arrival they gave Shep some new biotic amps yeey, which explains why she has them again as a sentinel. For some reason cloak is apparently exclusive to cerberus tech, so shep loses that but gets some tech abilties thanks to that new alliance hardware others have had for decades. Despite sentinel not being made for it I will remain to make extensive use of weapons such as AR's, snipers, and occasionally a shotgun, as per tradition.

If ME2 Adept + ME3 Vanguard it will go something like this:
In ME2 sheps biotics have become even better, which shows in the usage. Only Shotguns are somewhat 'not her style anymore'. On the collectors ship she'll add AR's (Mattock ) back into her arsenal which brings back her effectiveness at medium range. 
In ME3 she changes her style to be more aggressive (Vanguard) as she'll, complementary to her trustworthy AR and pistol, bring shotguns back and caters her biotics to more aggressive tactics. 

Now, I think for immersion reasons the latter option, for this playthrough, will be better. Gameplay-wise people might think the former is better and more fun, or not. Please vote what you'd do if you were mentally unstable me!  

Thanks!