Hacks aren't accepted anymore?

[Superjustinbros]

That and plenty of hacks do very little changes to the point it's not really worth submitting. (Such as zones being nothing but recolours and minor gameplay changes)
A hack that has major changes in art, gameplay, or anything else? Hacks like that have been pretty much the only ones that have been accepted.

Seconding this. Some are character swaps, some are level swaps, others feel almost like new games with the amount of content they edit/change.
I guess it's all based on how different the hack is from the base game and if it's not blacklisted or requested to be removed by the hack's creator.