Genoa: Best for building a trade empire that spans the whole world. Hansa is fun, too but it's always the same and you are op as hell.
Venice: Starts reasonable strong not OP though, grows weaker over time because NIs. Love to play them and let vassals do the fighting. Also Monarch-Point monster. No other tag can farm them like Venice. Probably best for playing a vertical game, which i like.
Friesland: Republican start, later NED
I find it hard to really like any ROTW tag for more than 1-2 playthroughs. Either you start out overpowered outright (Japan, Bahmanis, Ming, Timurids....) or you will be after 50-100 years even if you take it slow because there is usually only 1 big target to take out, after which you take its place and end up westernizing and doing a WCesque game. North Africa is an exception but that's almost Europe. In Europe you just have more options. The first years as Japan, Daimyo or one of the Indian God-Kings are a blast though.