[4e]Homebrew Dilemma

[Howler Dagger]

So, has anybody played Titan Quest? I plan on making a non-essentials class based of the Defense Mastery, called the Defender(you dont need to have played TQ to understand this though). You can guess its role. My problem is thta one of the major parts of the mastery was adding shield bashes to your attack, and im not sure how I could integrate that into the mastery without making it too strikery. For eample, taking direct inspiration from the game you could have a power that would deal Str mod+[W]+ shield damage. Also, im not sure how much damage a shield should do, but im thinking 1d4 light shield, 2d4 heavy shield. I also need an idea for a marking mechanic
My ideas so far:

Add an encounter power (maybe class feature) that as a minor action yoou can add shield damage to an attack

Deal shield bash damage to marked enemies

deal shield bash damage on crits

Mark enemy that hits an adjacent ally

For refrence, here (http://www.titancalc.com/TitanCalc.asp?mastery=Defender&master1=5&master2=0) is the defense mastery

[Mindfreak]

How about something like this?

A little something like Hunter's Quarry, where you can mark target as your 'Quarry'. Once per round you can use a bash attack on your 'Quarry' as a free action(or immediate interrupt, whatever) whenever they attack someone that isn't you. This shield bash would be Str + [W] + Shield Damage, or Str + Shield Damage and have a chance of making the target dazed(or stunned perhaps?)

That's just my suggestion.