on the second day of christmas my ds gave to me
another wr reroute
Said reroute was: doing 6 fewer levels at the beginning to buy world 3 instead of world 4. This required me to do two or three additional levels in that world, but this was still a net gain, partly because I avoided switching between action and puzzle on the level select two times. This run also incorporated the timesaves that apply to the unrestricted any%: some minor skips in tutorial, and doing action levels instead of puzzle levels in world 10.
Through some accidental research, I have found that it is possible to farm money using a custom level created in the level editor.
There are some caveats to go along with this for speedrunning, namely that there is nothing stopping you from playing levels created on another save file with access to