I would have to agree that the A3000 is by far the best Amiga ever. Sure the A4000T had IDE and scsi, but the scsi was just a Zorro card. Its built like a tank. Solid, even over the A4000T. No problems with mine once I put all the new chips in it. AGA is not all that. If you have a graphics card, who wants to run AGA?
The worst Amiga to me is the A600. It came to late. It wasnt that easy to upgrade. All the CPU accelerators are hacks that snap over the 68000 chip. It would have been better to just keep the A500 in production if they wanted to have a low end games amiga.