I think the next two years they need to stabilize operations and house placements. I'm sure we won't get to keep SS12, and we may possibly lose Mummy in the near future if expansions on the lower lot continue. Simpsons going away may be another factor, but it's oddly out of the way (at least the ride is), but the town getting a makeover can hopefully be done throughout the year it happens not effect HHN too much. Terror Tram is working great as it is right now, it can stay that way for the time being.
Just in general, they need to reclaim that SoCal throne. I feel like the verdict is out everywhere I read that Knotts is the place to be again and while FF & Dark Harbor are around, quality aside, it's giving people simply more options. The excitement for HHN is over. Find their groove again, ride that wave for another 2 years, then think of expanding (Metro lot would be great). I think that's 2028 at the earliest, 2030 more realistically.