Its rather simple really, make at least 3 versions of each boss floor similar to the clock work and set it on a rotation. "But wafflecone how would this balance out vanduke?" Well what the developers should do is find the average crown pay out for each level for a boss besides the actual boss fight and add some were from 500-1,000 crowns to it. This number will be maximum pay out that the floor can have for that set. By doing this some floors will have less pay out then others so you won't be getting a constant 7,300 crowns for vanduke runs but have the CHANCE of getting 8,000.

Just to clarify this idea lets say the first level, lets call it Watermelon, gives an average pay out of 2,000 crowns. Add 500 and you get 2,500. Now any floor for the boss in the same level rotation as the first boss level, Watermelon, can not be any more then 2,500 crowns and should probably be lower then 2,000.

The average pay out can be found by doing 5 runs on each level and then dividing the total crowns gained from all 5 runs by 5. So if you made in total 10,023 crowns the average pay out would be about 2,000 give or take a few crowns.

"But wafflebutt how would this make doing boss levels more fun?" Less repetition, you won't be playing the same 4 or 5 levels over and over and over and over again. The only level that will be repeated indefinitely would be the boss and they could COULD make slight variations to each boss level for look reasons but that is obviously not important.

The only issue I could find with this idea is the shadow lairs but I feel that we don't really need to change them but it could happen.