You can turn sense "on/off" on any sense phone, but all it really does is run the android launcher, its mostly only visual.
But I would suggest just that, see how you like it first. Right now there aren't any ROMs or tweaks for it yet. A lot of it has to do with sense, since its not open source, but the android part of it can still be tweaked here and there, as well as the kernel.
I'm still not convinced on overclocking the snapdragon, people seem to be able to run it fairly stable at 1.1XXghz, but the advantages don't quite yet out weight the risks IMO.