Originally posted by Snow ☯:

ddAnxjGzLp Here's a seed for you. Contains all the biomes connected to the starting location. No boat needed. Contains all the bosses. There's a tiny bit of water separating the land-masses that amounts to a dirver, which you might be able to build a bridge over.

That is a nice seed, but, as others have said, I think that might actually make the game easier rather than more of a challange, other than Yagluth, of course.

I think I found a good seed that is likely not too much of a challange, but looks like a good initial seed to test the concept with. I'll post info in a bit in case others might want to try it out.