Overall its still pretty great and i think the majority of people, those that want a shooter with some RPG elments, will enjoy it more. Personally though i wanted a RPG with some shooter elements, so for me the sequel has taken a step in wrong direction.
You'd have to play extremely efficiently (run everywhere, spacebar through every conversation/scene) to get a significant part of your playtime into shooting ... just like ME1. Hell the shooter missions felt longer in ME1.
It never was a good shooter and it still isn't .... all the weapons for which you don't run out of ammo every 5 steps are extremely spray and pray, the starter assault rifle is painful to use with it's 5 shot bursts, you can literally blow an hour playtime worth of missions worth of heavy weapon ammo drops in a couple of seconds, playing it gung ho and just relying on medigel does not work (because like your heavy weapons ammo your medigel doesn't get replenished between missions). The first sniper rifle you get runs out of ammo even faster (then you get to enjoy one with a decent ammo capacity for a while ... then the game fakes you out by delivering a new one again, but making it have 10 bullets again ... YOU BASTARDS).
Making ammo a limited resource is batshit insane ... the overheating mechanic was not what made ME1 bad as a shooter, it was actually an asset. It might have needed a little tweaking but it never annoyed me nearly as much as the ammo has in ME2. They should have kept overheating and made medigel/heavy-weapons ammo refill after every mission.
The weapons and shooter part of ME2 is no better than ME1 ... it's a little give (accurate shots without points in weapon use) and a huge load of take (unsatisfying weapons and ammo annoyances). In the end I think it's worse as a shooter even. Also there is still relatively little of it so the FPS fans will still not like it.
The dialog is okay, but god did they have to make the romance options so extremely fucking obvious? It's just a never ending stream of pickup lines and hugely flirty behaviour (right from the start) spread out evenly across game (it is literally impossible to talk to Jacob as a female Shepard without flirting with him).
The entire skill tree has been raped, everything interesting is gone, there is nearly no synergy, the skill tree capstones are OMG underwhelming. Also ammo powers are buggy. Squad members use them (even if you set the game options such that they shouldn't use powers at all) making any type of tactical decision with them moot. When the sensible behaviour would be for squad members to never use ammo powers without player intervention. Especially fun with squad ammo powers ... "oh hey Shepard, I see you activated your Disruptor ammo squad power and we are fighting geth ... how about I activate my ammo powers as well, they don't stack after all." I have the feeling they were meant to stack, but in the rush to rip out everything fun and synergetic in the skill tree that had to go too ... pity they forgot to adapt the AI while doing so.
I get the feeling they were told 6 months ago "make it dumber and make sure nothing the player chooses makes any real difference whatsoever to combat difficulty ... oh and make it more like shooter!!!" by EA.
PS. the pistol is still the best weapon, it's the sniper rifle ... just without the zoom.