There is den bitre dudes who use husakarls shield and they do fine. King glype and sultan eren are best example of hoplite players.
Board shield is nice for cover,there was one guy petar who used it in duel server and he was annoying as fuck. To bad it doesn't realy fit into any ropleplay
and it is ugly,but exept of look it is pretty fine.
steel and plated covered shields are nice for dtv game mode,i will use it there when i get 6 shield skill.
heavy round shield is not common,but it is still good shield,and ppl use it.
knightly heather shield can block arrows from sides,it is so knightly shield. Fits perfectly.
Brown Lion Heater Shield is also nice and fits knightly theme,Green Crescent Heater Shield is also nice shield i saw few horsmen use it.
Steel Buckler were used by Mala and cora,and it is used moustly on rageball or siedge.
So there is other good shields as you can see,and they can fit a lot of themes,it just depends on your playstyle and what you like to have.
I love speed so i waill always pick elite cav shield because it have 103 speed,and it is light.