I think you're getting the 288 MB ram from the specs (it's the size of the chip, I guess, but not the amount of free program memory); that's not the available ram, though, in use. I have no idea how much free ram I had on the stock fuze rom, but it wasn't anywhere near 288. I currently have 197 M free ram with a 16 M page pool on a 6.5 rom. Your ram is perfectly normal, it's what everyone has. Flash back to the stock rom and see how much ram you have then-it won't be 288. (Now that I think of it, I think I had ~200 M free on the stock rom.)
There's no error in the % ram at startup, either. That is entirely by design. If you want to see a lower number, use advanced config to either lower or disable the caches. Then enjoy the low program memory usage and the sucky experience. More ram usage = better performance. You still have 110 M of free ram at startup. That's more than most devices have in total. Use it. Enjoy it. Don't waste it by not using it. That is my advice to you.
If you don't believe me, just take look at NATF's 6.1 rom
vs. his 6.5 rom
. He's got 193 M free ram in the 6.5 rom (with a 20 M page pool), and 200 M free ram in the 6.1 rom. Not sure what the PP is in the latter, but I suspect it's 16 M. You can also look up stock or stock-like roms in the rom forum. They're all going to be in the same ball park, depending on the paging.