What feature do you want to see added?

Run a current minecraft server with mods and decent and well supported World Protection and World Editing features, namely: World Guard and World Edit/FAWE, which only would be a decent option with FAWE supporting Sponge or Forge again.

Are there any alternatives?

At the current state there are only three undisirable alternatives:
-Go back (or stay) at a very aged version for mincraft (1.12.2) where you have anything available
-use Arclight, which only few people even know and even fewer recommend
-use Smaller, obscure protection/editing mods from forge, with like no support

Anything else?

Thank you!