Usually i use shiki themes and elementary from time to time. They all have the same issue. I think that's metacity perk and not theme related. Recently I became switched to LXDE (try it on High Performance PC - Mind blown) and i don't have that problem as openbox has nice borders and handles.
Try holding down <Alt> and middle clicking anywhere near the window corner, I find that far faster than trying to grab any kind of corner or side, and I get frustrated when I have to use an OS (eg. Windows) that doesn't support this.
