I spend the absolute least amount of time in Tomorrowland. I don't do Astro because of my slight fear of heights, I skip Space Mountain because it's dangerous and scares the crap out of me, I skip the Speedway, I skip Stitch. I don't do the Laugh Floor, not because I dislike it, I just bypass it. Buzz/shooter games do nothing for me. So ... yeah. Tomorrowland is a bust for me and needs the overhaul more but I recognize that's me and many people love all of the above.
Frontierland doesn't need the help or really an expansion. Adventureland could use an expansion before Frontierland, just for the sake of the crowding (the Carpets were put in the wrong spot, that's a LOT of space that could be used to shuffle guests around). Frontierland should be last on the list, but it will eventually need something to free up the walking space.
I've always felt our Frontierland was slightly weaker than the others, not as much to explore (unless you go to Tom Sawyer Island), just a long strip mall, there needs to be more areas you can escape into and look around. Like instead of the railroad station being where it is, build a new station and expand that way, like where the Golden Oak Outpost is, just off-the-path areas to get away from the gridlock.
The two e-tickets are fantastic (Big Thunder is overdue for a plussing) and I love the Country Bears. Expanding behind the Rivers, not on the river, would be ideal and then connect you to Liberty Square instead of the dead end by Big Thunder.