Have you played Knights of the Old Republic? Same developer. It's like KOTOR, but with a different combat system and an interesting, Larry Niven-esque future and a plot that's something like an episode of Star Trek meets H.P. Lovecraft. The graphics are occasionally choppy but all-together beautiful, the main story and most of the side-quests are interesting, and the voice-acting is rather good for a video game, make of that what you will. It's got a deep character creation and level up system that actually effects some of the dialogue and minor plot points of the game. The characters all have subplots and different motivations and open up new quests depending on how you respond to them. It's very creative and ambitious enough to love despite its flaws.
There were only a few things that irked me, and most of them had to do with weapons and items and inventory management.
The inventory management system is painful; deleting items is a chore because if you arrange them according to level so you can easily tell what might be useful to your characters, it puts that lame stuff at the bottom of the list. That's fine, until you delete one of the last items on a list of 50 items (which you will quickly discover is an easy thing to accumulate) and the cursor automatically goes back to item number one and there is no quick scroll. You quickly collect either more shit than you can use or more than you can convert into the material you need to make bombs and first aid kits and buy upgrades which you almost never need to do because there is shit to be found everywhere. There are locked boxes and chests all over the place and enemies drop their weapons and items too. At about 2/3rds of the way through the game I found myself simply dropping a lot of stuff on the ground because all I was getting was low level crap and my material was maxed out at 999 all the time. There are simply way too many weapon and armour power ups as well. 90% of them are useless once you get the handful of awesome ones and you, again, simply end up passing on them constantly. Why use a "level six" upgrade to your armour that provides a 20% bonus to projectile damage protection with no penalty when you've already got a "level five" upgrade that provides 25% protection from ALL damage with a measly 5% hit to my dodge stat? Stuff like that makes me think these guys have a big "power up wheel" that they spin to ensure the appearance of variety under the guise of sheer quantity. Even with 6 characters and some armours and weapons that have 2-3 slots each and cumulative stats the vast majority of items you get will be either useless to your characters or crappier than what you've already got.
I also found the planet-side driving pretty boring and repetitive unless there were things to shoot at, which there tended to be only on the main-story path-driven levels. The open world type levels were much less interesting, and the missions rather repetitive in action if not back-story. To be fair, it only gets repetitive if you're one of those people like me who tries to 100% clear games like this. I only cleared 80% of the game on my first pass, haven't played it again yet.
There is a lot of reading you can do on just about every aspect of the game: races, politics, technology, history, etc. It's all entirely optional and either very interesting if you're interested in the "world building" aspect of science fiction like I am or very boring and pointless if you're someone who prefers to hurry through your games and get straight to the meat of the story and the action.
I do recommend it quite highly. The game does give you a bit of a feeling for what it might be like to live in a future with 1000 km long space stations and FTL drives and aliens waring and trading and living with one another. It's one of the few recent attempts at what one might call a true sci-fi game. Most are mixed with horror or are only sci-fi in appearance, but Mass Effect is sci-fi to the core.
On the subject of the thread I'm most looking forward to SC4 (Mitsurugi FTW I'll kill all you bitches!) and Too Human.