I’d say the biggest two DLC packs (Rise and Fall, Gathering Storm) can be worth it; though only on sale. They add a new era score system, natural disasters, and global warming. I bought Civ 6 in its platinum bundle (more than half off), while I like having them had I paid full price I wouldn’t have been happy. If you don’t want to play with them after you get them, you can still toggle them off at the beginning of a game. Then there’s individual civilization packs; if there’s some that interest you/come in a pack, that’s great, but you’re just getting one or two new civs to play with there. Don’t have the New Frontier or Leader Pass stuff, that’s in the anthology, but I’ve heard the Leader Pass doesn’t even run right on Mac or Linux. Hope this helps you out, definitely wait for the summer sale though!
Looks interesting; one of the things keeping me away from some FPS games is the sheer amount of micro transactions. I’d spend 15 and get something good and fair for everyone who plays instead of being asked to put in another purchase every few minutes!