@Hykal94
If I were to get a single DLC, which one should I get, knowing that bandit raids on my settlement are my least favourite part of the game?
Well, if you dislike dealing with raids (which you can disable via the scenario editor BTW), then Royalty and Biotech makes them easier by giving you more tools to deal with them as the others have said.
Royalty not only gives you psychic powers, but also new armor and weapons. Biotech does add new raids in the sense you get raided by Impids, Neanderthals and Hussars but you can also recruit them yourselves or make your own horrible Thunder Warrior abominations. Similarly, Biotech adds new Mechanoids which you can make and fight yourself.
One cool challenge Royalty adds is hosting Royals. You not only have to make cool throne rooms, but also high quality bedrooms for yourself and your guests. Now, it is a common complaint players don't want to host the one Duke and his 15 best friends but this 100% adds a new dimension to the challenge by forcing you to build bigger bases. But these are quests which you can very much ignore.
If roleplaying is your jam, Ideology, hands down. Not only can you make weird wacky cults, you can also make it easier or harder on yourself. If you want to make it so you don't care for corpses or you don't mind eating nutrient paste, cool. If you're in the Liver King diet and only want to eat meat, you can too. If you wanna be cannibal free love tree worshipping hippies, you can! It arguably has the least impact on combat overall.
Anomaly is the one DLC you do not want. It is very much the Dead Money expansion of the series. It is tight, focused, and extremely combat heavy. Either way, you can't really go wrong with any of them.