With Cedar Fair cutting back on major capital expenditures (i.e. coasters), it sounded like CF was going forward with adding only one major coaster per year in the chain; at least for the next 3-5 years. I consider a major coaster costing over 18 million dollars.
I think you could get a reasonable mid-sized coaster in the 12-17 million dollar range. Course, the RMC raptor and the Infinity coasters at Cedar Fair's California parks probably fit in that price range. So, I guess it is possible for another CF park to get a coaster for 2020.
Given the land clearing going on at Kings Island right now, it looks like they are the CF park getting the major coaster for 2020.
I can't shake the feeling, at this point, that CF/KD are going the "generic" route, whether installing flat ride(s), a dark ride, or even another coaster on this site. I think there will be a themed structure on that spot. I don't know if it will be another mountain or something else.