the regular gtx 750 superclocked is very close to the 750ti, but there's not much of a price difference. Either will be nice on a budget to get you started. Just turn off the taxing msaa, it kills fps.
I snagged a gtx 660 cheap recently due to BSOD pointing at AMD driver problems even on a clean install, it's a really nice gpu for not that much money these days. It's on par with the hd 7870, which I tested before, and it got 60 fps constant in bf4 64player conquest on 1080p ultra (no msaa) with my stock i5 3570k, and since the 660 is on par with it, the 660 is no slouch at all.