I'd like to see something similar to the MP chain of chests, but in a format of generating a random SP map+enemies in progressing difficulty up the purple chest. I often want to grind some CH while I'm doing other things, but the time constraint and other factors make MP often tedious. It could easily fit into a CH scenario: The hedge-wizard Aloyzo has opened a portal to another dimension in dank depths of the dungeon within his tower, go forth and close the gate! With the last map "closing" the gate, until the timer resets, in the same way that the purple MP chest resets.
I like this idea. I'm more of a SP than an MP guy, so having something other than MP as a decent way to grind gear would be very nice.
Could be a decent possibility for extending singleplayer experience. Although SP is already far superior in terms of item amount.
I also support the OP's idea. I would like a SP game option with shuffled maps, random mobs and a loot-ladder difficulty progression.