Yup, looks like they just want the Mini dead and gone.

I don't understand where the turbo JCWs fit with the new classes. Right now, they are near the top of STX which has a pax of 0.822. So maybe their real pax in STX trim should be something like 0.823. With 50-75hp more, they should get a pax in STR/STU range near the .830 level. That would be .75 seconds over a 60 second course.

With the mini removed, I think the pax of the new STH class will be closer to the current STX 0.822. Nothing in the class competes in STX. Of the non-RWD, non-Mini trophy winners at nationals since 2013, you see 1 Focus ST and 2 Acura Integra Type Rs. Out of about 70 trophies, only 1 went to a car in the STH class. With 50-75hp extra, they would compete in STX, not ~STU.

It looks to me like the mini is too fast for STH, to slow for STU. Sort of like the Boxsters that just got added to STU. Am I reading the situation correctly?

Seems correct to me. They hobble any mid engine car in STU with 255s as well which kills the Boxsters dead.