The A1000 is great for running older software. It is fairly easy to get Kickstart 1.1, 1.2 and 1.3 disks that will run software the may not run on newer machines. Granted hard drives may be a problem, unless you can find an A500 sidecar GVP, Supra, etc. They will work with 1.2 and 1.3 Kickstart.
I love the A3000. Great machine! What else can I say?
I also like the A2000 a lot. With at least an '030 accelerator they accept a multitude of Zorro II cards, and the Video Toaster. In the past I have had an A2000 running 3.1OS, and Windows 98 (with a 386 Bridgeboard). There is a lot that can be done with the A2000.