There are 3 addons for slimefun that could be cool; Barrels (not 1.16), Soul Jars (not 1.16), SlimeXPansion (not 1.16), Chest Terminal (1.16) and Hotbar Pets (1.16). Also can you try and fix slimefun please because I think that a lot of people are wanting that so they can use slimefun. I will change (not sure) to (not 1.16) or (1.16) when the developers of those addons respond to my question.
Links for the first 3 are in the comments, new links are here https://github.com/TheBusyBiscuit/ChestTerminal and https://github.com/TheBusyBiscuit/HotbarPets