Mountain Peak? Haven't heard plans of an update. ISI has been going through the existing tracks and updating graphics to their new standard (plus any other fixes as necessary), but now that Portugual v2 was released, I don't know which one is next. You're always free to make your AIW and, if you asked around, you might find someone already made one.
How are Howstons broken? The only two things that come to mind are the early AI pitting due to fuel (turn off fuel usage as a workaround or just pit when the AI pits the first time & you'll be on the same sequence) and the silly slipping clutch (just use autoclutch as a workaround) in place of a real drivetrain solution. I wouldn't expect an update for the Howston until after the stockcars are released.
ISI has, at least for cars(*), announced they will update old cars with CPM and alternate with new car releases. DW12 Indycars were just updated, so the next car update/release will be something new. Everybody expects the new car release to be stockcars. Since it looks like there's one more change in the core code required before stockcars are released, it could be we'll have to wait for the next rF2 build. Or it could be that one of the other announced cars will be released next (Eagle, Nissan, Maverick, road-to-Indy), then an update to an existing car, new rF2 build, and then stockcars.
(*) Track releases appear to be following this pattern, but I never saw an announcement that they would.