If you own, I'd suggest giving it a try. It's much better than many reviews would suggest, and I really, really enjoyed it. If you're into something war-oriented (WWII), maybe look at The Saboteur. I found that one a lot of fun. If your rig can run it, you might give ELEX a look as well.

Well, Saints Row 4 is a parody of Mass Effect. That could be cool.

And if you liked KOTOR, try KOTOR 2, just make sure you get all the unfinished content patches for it.

It's a tough ask for anything to follow the Mass Effect triology. But if you are after games with a great story/concept then you should check out the following:

Bioshock 1, 2 and Infinite
Quatumn Break
SOMA
Sleeping Dogs
GTA V
Metro 2033 and Metro Last Light
Spec Ops: The Line

Deus Ex: Human Revolution is a class game - no doubt you'll have fun with it.

Kotor 2 is an excellent choice, as are both Deus Ex modern games. Warning, Deus Ex is far more linear than Kotor or Mass Effect, but the games are pretty solid. If that works for you, Shadowrun Returns, Dragonfall, and Hong Kong are all good choices as well for the sci-fi choice making itch. Those are Extremely good for that cyber punk rpg niche.

Get all the Saints Row games. They will absorb you. I played them and turned into a giant man-cat.

/waves to Professor Genki - UNETHICALLY!

On topic - Alpha Protocol is great. Extremely underrated IMO - a few bugs bug I never experienced anything gamebreaking

Be James Bond, Jason Borne or Jack Bauer - the choice is yours!

Deus Ex Human Revolution and Alpha Protocol are both good choices I think. Gameplay in Alpha Protocol is closer to Mass Effect, being 3rd person and all, but DX HR is by far the better game in my opinion, AP can be pretty unpolished at times. Still worth playing though, the story and choices work pretty well and its a setting that isn't as common in games as Scifi.

I've only played the first DX and while I liked it, I always considered it a shooter, far removed from anything RPG like the other games being mentioned here. Do the later games in the series swing more toward RPG?

RPG, not RTS.

it's been a long day :P

Well, you can only go uphill from here.

I suggest Actraiser.

Depends on the individual play style... I rarely use guns in DX games, they just clutter the inventory ;)

Assuming you mean RPG... they're predominantly a hybrid of FPS and Stealth games of course, but all have a levelling and/or upgrade system, lots of choices, side quests and different paths to take, an inventory like said, and tons of dialogue too... id say that qualifies as RPG, similar to Mass Effect 2 and 3 at least.

Bump for Bioshock Infinite. If you liked the RPG-shooter gameplay of ME3 it seems to me that Bioshock Infinite is right up your alley. The scale is smaller, so you don't have the whole "save the universe" thing, and the game could really use a Tali'Zorah or a Legion, but still I think you should give it a shot. I would bet that whenever the summer sales start you could pick it up for $10-15, tops.

Maybe Borderlands 2. It's a RPG-lite shooter but if you enjoy playing co-op it's excellent, and though the world is comical instead of bleak, it's just as well put together. And it's very comical. If you think you might like Saint's Row (and I did, sure. Who doesn't like jumping out of a plane that's actually a giant robot eagle that screams the Star Bangled Banner and shoots lasers from its eyes, then landing in a crowded street and beating people to death with a giant dildo before switching to a dubstep gun that makes people dance erratically then explode. Everyone likes that, right? Tale as old as time. Especially the murderdildo.) you should check out Borderlands 2.

Oh, and let me - once again, because I'm a broken record - suggest you look at ENSLAVED: Odyssey To the West. Highly underrated. Tight story. Good gameplay. Amazing graphics for its time. Plus it's usually about five bucks when its on sale, and sometimes half that.

I played a game on console called XCOM: The Bureau. It wasn't a bad game at all, with combat similar to the Mass Effect games (squad based, real time with slowdown tactical combat - heck it even had shields, flanking and a power wheel). Not quite as RPG like, but still some character progression and side quests, plus some non-combat downtime in your base where you'd have conversations and do various other tasks.

I enjoyed the game - pretend it doesn't say XCOM anywhere and just have fun with it for what it is.