Berbers are in a good state they just have some old design choices having 2 team bonuses one of which you have to research and the other one you rarely see used.
First change i would suggest is making Genieors a regional unit for them and the two Iberian civs. Spanish get ones that attack faster and Berbers either more faster or are cheaper. The only civ i see use this are the Turks and Meso Civs, we also have two skirmisher team bonuses with the Viet around
For the new Team Bonus i suggest removing Kaspa and making that the team bonus though probably nerfing it to 15%
Now or the new Castle Age UT. With the naval changes coming and boarding ships being added i think its time to get some Barbary Pirate. UT Corsairs: Infantry and Hulks generator gold well fighting
Non of the civs seem to have a bonus for the Hulk line and Berber are one of the civ that would be perfect to be given a bonus for then on top of their civ bonus making them faster!