Hey, it’s your system so you should house it however you want.
Personally, I prefer the original cases for that authentic look and feel, although I think the Checkmate achieves that, too. But I don’t see much point in a larger case for the wedge Amigas unless you’re also adding a Zorro or PCI busboard. That’s what all that extra space was meant for! If there are replica original cases on the horizon I’d wait for those.
Also, unless something's changed in the last few years, I don’t think there’s been an A500-compatible tower case produced in decades (other than one-off custom ones), so finding one is going to be tough tough tough.
