I remember really, really wanting an Amiga 4000T years ago. It just seemed like something to upgrade to as I had an Amiga 600 at the time. I didn't know much about the hardware because I was only young but I just remember seeing them in the backs of magazines and thinking wow, its got 4000 in the title, that must be so much better than mine.
I think what I'll do for now is spec an Amiga 1200 with the ethernet, e-matrix card and a HDD and maybe the IDE-Fix Express Buffered IDE (would Amigakit fit this for me?) if that helps performance with the HDD any and then if I really get bitten by the bug buy some parts to try and construct my own all singing and dancing Amiga 4000 at a later date. That way I'd have a professionally built system that works and then another one that would probably be unreliable but a lot of fun to tinker with.
The card reader also seems like a good choice as well so I might pop one of those in. With regards to the PS2 adaptor I think I'll leave that for now. I still have my old mouse and whenever I click with it the sound sends shivers of nostalgia racing through my brain. The indivision aga as well isn't so crucial because I do have my old monitor still from when I had the Amiga 600 (complete with Ninja of the Nth Dimension, Zool sticker set stuck all over it which has now saddly begun to fade.) I have a whole host of joysticks as well, but I think only one of the Quick Joy's work. I used to love the Cheetahs but I think I went through four of those and they all broke and my parents refused to be any more.
I'll also leave the CD drive for now as well.