They did say they will use the counc to vote thr new king every time. Which was similar to sams idea of democracy.
Plus bran can see things in advance which no king can do. That alone can be advantegous to the westoros. He can see if people around him are telling the truth. That alone is huge. No king could do that.
Ps hes on the wheelchair. Hes paralyzed below the waist so thats a dead giveaway he cant have kids hahah
The funniest part to me is that the solution to the series was putting an uninterested king on the throne with an unclear line of succession.