So, I was thinking about the mess we have known as Adventureland. The walkway is too narrow, it feeds Indy and JC, two popular attractions; and guests use it as their primary route to get to NOS/CC. Nobody goes through Frontierland.
I wondered how it might work if the Adventureland Bridge was removed and took over the Frontierland Bridge. Now hold on a sec...let me explain.
Adventureland would expand upwards into part of what is now Frontierland. Maybe theme the Golden Horseshoe to The Adventurers Club or something along those lines. Why do this? Well, guests would be using the wider street as a means of walking and it would help cut down on the crowding of the attraction portion of Adventureland.
So what happens to Frontierland? Carnation Plaza. The large stage area to the west of the castle which connects to Frontierland. The large EMPTY stage area. This space is rarely used. Make this the entry way into Frontierland, theme it in the same fashion (like a old west town). With some minor adjustments in the layout of the northern Frontierland buildings(Shootin' Gallery, etc) a nice walkway can be formed spilling out in front of BTMRR and the Rivers of America.
OR...move BTMRR to Tom Sawyer Island like Paris, free up that land, allowing Frontierland to spill out where BTMRR currently is allowing much space for another Adventureland attraction.
Okay, that's my wacky crazy improbable never-gonna-happen idea.
Another less crazy one is using Carnation Plaza as Wild West Show. They would obviously cut it off from the hub and disquise the exterior of the arena with trees and castle walls. The show would be accessed through what is now the Shooting Gallery. I think a simple Wild West Stunt Show would finally give Frontierland some energy and life back.