Just to give you something to think about...
I've done view camera work in the long distant past, and I always desired a tilt/shift lens for my SLR's, but I never bought one, mostly for reasons of cost/weight/bulk (as you can tell from my signature, I'm a minimalist). Fast forward many decades to today, and I'm finding I've finally got enough robust pixels with my K-7 (my old Nikon D100 didn't cut it in this regard) that software perspective correction is now totally viable, in fact remarkably so. I use it often, and the resulting images are not degraded at all from all the pixel shuffling, at least not that I can see, and I'm pretty critical. It works so well that I no longer desire a tilt/shift lens. As for your question about closer-up subjects, I guess I haven't used software perspective correction in that way, but it would certainly work just as well.
If you are interested in my methods, I use Photoshop CS5, place a grid over the image (command + apostrophe), and use Edit>Transform>Distort to make my adjustments. The grid helps enormously.
Here's a few examples, although it's hard to tell much about image quality from these little JPEG's. These all make beautiful 13x19 prints - no one would ever guess they have been "manipulated" in such a way, they really look great.