I been playing a Mace/shield warrior, I really love what the have done with the shield in Skyrim, granted at the start of the game the shield is pretty much like Oblivion but as you invest more and more perks into block it become so useful and fun to play.
As for spellbreaker, I had that shield for a while now and its just plain awesome, only time I don't like it is when you get bombarded with elemental spells and the ward keep breaking and constantly staggering you.
I don't really like the mace of molag bal, sure its a powerful weapon you can get at a low level, but with 100 smiting my ebony mace do 78dmg vs malag bal's mace at 67dmg, the enchantment is crap to in my opinion, I'll take a fire dmg or absorb stamina enchantment over damage magicka/stamina/soul trap.