Most mods shouldn't require the dlc unless they are based around it. Royalty is very good and add a lot of game play improvements like high tech melee weapons and psi powers. The system around psi powers is innovative and new. Boitech has cool new races with specialities and weakness. You can get very overpower with the right combos. The mechs are super disappointing as their unique drawback toxic waste is extremely had to deal with without cheese until late game when you can magic it away with some difficult to obtain parts. Ideology has fun ideas and roleplaying potential but it's implemented in a meh way. It's nice to be able to say my colony doesn't care about cannibalism or likes nutripaste but it doesn't add much beyond that. I haven't played the new horror one. It doesn't look very good. I'll see what kind of reviews it gets.