GTA V has a lot more variety to offer on the missions, and yet more variety in the overall world. After a long session of criminality, I like to unwind with a nice 9-holes of golf at (more or less) the Los Angeles Country Club on Wilshire. It's a nice little mini-game, and my one complaint is that there is only the one course. (I've played a little bit of GTA online, and while I might as well be a paper target in the gunfights, I'm undefeated at golf.)
An even better addition to the missions are a small handful of heists, which amount to supermissions. There may be some little side missions to get the equipment needed for the heist. And most of them offer 2 ways of succeeding at the heist, with different planning options, eg you can rob the jewelry store by a pretty straightforward skimasks and guns plan, or you can get some knockout gas and introduce it into the vents of the store.
The other big gimmick is that you now have 3 main characters to control. Usually you're only handling one at a time, following his little arc, but if you get bored of one, you can switch to another. And on some of the more involved missions, two or three of them can be on the job, and sometimes it's strategic (or necessary) to switch between them during a mission. Each has his own specialty: a driver, a shooter, and a maniac. On the whole it all works pretty well.
And yes, driving around 'Los Santos' is fun as hell, identifying all the parody landmarks. Cedars-Sinai = Mount Zonah. I think my favorite was driving down Vineland and running into not Ripley's Believe-it-or-Not, but Bishop's WTF?!
Yes, it's antisocial, crude, generally misogynistic, and one scene of torture really stretched the boundary a couple inches too far for comfort. I do think they fell down on not including a female character as one of the playable ones. I think the creators and writers, who are not dummies, and probably not (all) raving misogynists, could have really made something out of that.