It's at the mid/lower end of the Coolermaster price range but still a decent quality case: the
CM 690 II is less than
80 quid.
Out of the box it's not uber chilli, but that's nothing a couple of quiet 120/140mm fans can't rectify. There's no shortage of places to put them either as it can take up to ten.
It ticks all of your boxes; there's space for a dual rad, it's tool-less, has a cut-out behind the CPU, bottom mounted PSU with filter & it's priced low enough to earn some brownie points with the missus.
About six months ago I gave my son my old system, an A64 X2 4200 running @ 2.7GHz and popped it into the 690 II's predecessor, the vanilla 690, and it handled the hot weather the other week with aplomb. If I was building it now, I'd spend the extra 20-odd quid for the revised version without hesitation.
HTH.