Hey, big fan of your work. Dunno how busy you are or what stages you have in the works, but if you're receptive, I have a DK-related suggestion that I think would be both 1) popular and 2) relatively easy to make.
The stage itself could be set on a sunset ocean cliff overlooking Peardian's Crocodile Isle (https://www.models-resource.com/custom_edited/donkeykongcustoms/model/12474/
) in the background, in such a way that evokes the secret ending of DKC2.
The Kingdom Hearts stage 'End of the World' has a similar cliff model (http://www.mediafire.com/file/q2dwgnoei21/The+End+of+the+World.zip
), which I believe originated from Brawl's opening credits sequence.
If it's possible, the Flying Krock (https://www.models-resource.com/custom_edited/donkeykongcustoms/model/6608/
) could also circle around in the background above/around the island in a simple flight path.
Thought I'd pitch this idea to you, in case Abbey Ruins was an indicator that you're looking into new stage possibilities. There really aren't that many from the DK series on the Vault as is.