redesigning the game so that High level adventures are more controllable and similar to low level adventures is simply forcing high level characters to play low level games. There are real world example's that are applicable. When Navy Seals show up with all the tech and back up the US can provide it's not the same thing as sending in a company of Army rangers.
High level Characters are The superhero's of the world, they are Drizzt fighting 100,000 orcs or Raistlin marching into Hell to fix things. If you come up with a game design that put's it all on rails for easy DM'ing then it's not high level adventuring it's just characters with more hitpoints doing the same thing.