one thing i havent seen mentioned yet is that with the Improved Shield Bash Feat you can S&B even more effectively:
(from DDO Wiki)
Improved Shield Bash enables the character to retain the shield bonus to its Armor Class when using Shield bash, and grants a 20% chance to make a secondary shield bash while attacking with a melee weapon.
so that enables you to shield bash while turtled up without losing AC, which matters little to this build, AND
grants a 20% chance per swing to proc an offhand attack with your shield, which could add alot to your DPS while tanking. (shield spikes can be crafted on, as well as other damage add-ons)
[edit: looked it up. your best best for going the damaging shield route is a +5 Mithril Spiked Shield of Bashing. Shield Spikes shard and Bashing shard. unless shields come in Silver, then go with Silver rather than Mithril. And if you wanna get fancy add on a Force Damage Alchemical Ritual too.]