We could definitely use a bigger cap on the max # of friends. Just think about how many games we have on the blizzard app and besides that, the same person could have smurfs (I myself bought 2 WoL copies so I have two accounts).
It’s pretty easy and often that people add more connections to their friend lists, as a lot of the games we have here can be played in teams. You add a friend’s friend and it just continues from there. And when you reached the limit, it’s quite frustrating and awkward you have to remove someone (randomly?) in order to make room for a new friend.