I would back another Playtonic Kickstarter project; I really enjoyed Yooka-Laylee and it was without a doubt worth my money.
I had hoped their next game would be funded by the profits of Yooka-Laylee, but I really don't know how realistic that is. I'm not sure what to make of the huge delay on the Switch in terms of business -- it's certainly not an ideal situation -- and then we also need to wait for the promised DLC as well. Dare we even remember the Kickstarter promise of a live orchestrated soundtrack?
Lots of money being eaten up, and no word from Playtonic how much they have in the bank.
I do believe a second game will begin development, but I'm not sure what game it will be, or how it'll be funded. Let's wait (possibly 6-12 months?) and see what's announced.
Edit: http://www.gamesindustry.biz/articles/2 ... oka-laylee
This article confirms they are already working on other projects (although this may just been conceptually), and that they are (or want to be) self-funding.