IMO, Concentration is a wasted skill on TG. Untouchable force is pretty meh, and combat alert should never be made into a buff (esp. on consoles).
Get some RpH, your best source is a weapon as it will give the highest amount. Rings are OK, but kindof a waste in Silver as the values are not very good until you get into the 30's and 40's, levelwise.
Devout TG's are great tanks, and you should not have any issue with anything other than the fact that you can only effectively kill monsters one at a time.