An answer you may not want to hear, but from what I have read, the most bang for the buck comes from lightweight GUIs.
LXDE or so. PCLOS has one of the light GUIs, and that's probably where you want to go. One of the biggest resource-hogs
in any OS is the GUI. The other thing is to get rid of overhead software--stuff that's there, and maybe running, but you
never use it. If you loaded it, then unload it. If it defaults, then you need to find out if you need it for system operation or
not, and if not, then remove it. Look in Google for high-overhead software in Linux, and see if you're running any, and then
see if you need to. Top will give you a continuously running tally of processor use, and ps -a will let you read at your own
(I have not covered the obvious: faster processor, more memory, fast video card, and you might consider the less than obvious:
if the power fails, you will have to do over [if possible] so an UPS is good insurance.