1. Barbarian having a keep ? perhaps I don't know enough about Barbarian but aren't they a bunch of savages ? just provide a hut or something ?!
2. already not a big fan of the Paladin, you are suggesting that the reward should be to do some shift along some walls ... in an isolated place I guess ?
2a) why not promote the paladin to a lord where the "king" allocate a land and colony instead ?
...
It's not that you don't know enough about barbarian, or paladin, or cleric, but that you haven't played Baldur's Gate 2. He was listing the classes and strongholds in BG2. He also wasn't suggesting any "idea" specific other than that a stronghold idea in BG3 similar to that in BG2 would probably be nice. "Stronghold" is just a word people came up with for the building/faction that you become affiliated with based on the class of the main character, and you get a few side quests from it - quests you can only get if you play that specific class. It helps make your playthrough feel personal, and that your class choice matters. Whether your stronghold is a church or a hut or an entire region doesn't matter. You can have any sort of suggestion, but you're better off making your suggestion to Larian instead of to the OP.
It would be a nice nod at the history of the franchise
Well let's hope Larian cares about making nods "at the history of the franchise" then. But to be honest, I think the suggestions that some have been making here, while nice, are way too complicated to hope for.
