Other than lucky criticals Mass Effect is just the same as Fallout or Dragon Age or the Witcher 2, if you've built your character effectively you'll breeze through but if you've built a suboptimal (for combat) character you'll run into difficulty. That's nothing really to do with turn based vs real time. If you took Mass Effect 2 and made a turn based mod for it with the Unreal Development Kit the drones, barriers and biotic fields would work the same way and still be dependent on your build choices.
Which was my point. The fact that it's real-time (or real-time with pause) doesn't mean you just point, shoot and call it a day. There's still character-building and strategy involved.
And plenty of games have one hit kill weapons that can be just as annoying and probably more common than critical hits.
Well, the thing is most of the time one-hit kills in games are fairly obvious and are meant to be dodged. Think of the snipers in ME1; they could easily 1 or 2 shoot you, but before they fire you could see their painting laser. So you could avoid it. In Fallout I could not avoid that Super Mutant's gatling gun critting and instantly killing me whatever armor I wore. I mean, I imagine there are games with cheap one-hit kills, but as far as I remember Mass Effect has none of them.
Since New Reno is totally optional depending on your build at what point are you going there?
And how are you going to know it is on your first playthrough? You can hear about the city several times, and it seems like a pretty big place, and if there's one thing RPGs have taught us it's that everything is there for a reason and you should do everything you can, so that big city must be there for a reason. Of course, New Reno is actually one giant XP and money farm, but there's no knowing beforehand.
Also it is as well rather easy to run away from random encounters. Just run to the closest exit and leave the map.
Depends. In some of them you start surrounded by gunmen who can easily kill you if you don't have appropriate gear (and even then, crits happen). I know i was rocking advanced combat armor and the Super Mutant patrols around Mariposa Base still took several tries to get past. Friggin mutants.
Anyhow, we're kinda derailling from Mass Effect, don't we?