STR is a good option. There will be situations where you will DPS, and situations where you can DPS while tanking.

It's usually a good idea to keep some slaying/striking accs with you, for the DPS stats.

As long as you are comfortable with your HP pool and the heals isn't complaining it can help. Granted it's not a drastic boost to DPS but helps.

I have recently started to delve into it for my PLD since I have been doing it on my WAR.