Weirdly enough, I found that games like Witcher and Deus Ex made me feel MUCH smaller than GTA or Saints Row. In those games, I am akin to a god - people are flimsy, slow and obviously lesser than I. What I do changes the city and involves concerted effort by dozens if not hundreds to stop or shape me. They fail. They are weak.
In DX and W2, the characters are much more real, act much more like people than in GTA or SD, ( the civvies always seem like mannequins. Screamy mannequins), have plots and sub stories and in general draw me more deeply into the setting. Also, I'm much more killable in those games, not that it matters because a mindless kill spree feels as wrong in DXHR as it would in the real world.
So, yeah. I find GTA and its ilk, although fun, to feel much more false-front than Witcher 1 or 2.They all have obvious limits, the open world games just put them in different places.