[2.3 suggestion] "Episode" Select Menu for custom level packs
I think a SOC-customizable menu akin to Doom's episode select menu would be useful for custom level packs. Take for example, a theoretical Encore Mode level pack, which adds an "episode" which is selectable alongside the main story upon starting a new save file that leads to MAPE1 instead of the default MAP01. The unlockable level selects would be able to be locked to an episode, so normal levels would not show up in the custom episode level select, and vice-versa. Like characters and unlockables, you could Clear Episodes
in MAINCFG to only have your SOC-defined episodes show up.