They only ways I can think of selling it are:
1) Something like the MiniMig but packaged in a cute 'mini' 1200 case (and maybe mini 4000T cases) with the Amiga brand name, running loads of pre-installed WHDLOAD games. I think loads of people (ex-Amigans + some existing classic users) would buy into this but only if it was idiot-proof and cheap (<$200).
2) Replacement classic motherboards for classic cases (I can see only limited sales).
3) Replacement classic motherboards (with cases?) and some modern updates (think Natami), again I think they would sell but only in limited amounts.
Basically any classic upgade (OS3.9) will start to compete with SAM and the X1000 (OS4.x) if it's too expensive.