To be complete, a Templars maximum damage can be approximated with chance on hit mindblast and sufficiently high stagger on being hit.
The only true damage bonus that templars get is the dispel on barriers and buffs, but again those are mostly situational.
Besides we're talking about soloing, so necessarily for warriors this is strictly equivalent to killing high health damage sponges. The rest dies as collateral.
Actually I am thinking maybe 2H templar is the most difficult spec to do soloing in warrior classes.
SS champion, 2H champion, SS reaver are all good at soloing.
2H reaver is risky, but the burst damage is its adventage.
SS templar is also fine I think, although it will lack of dps when facing bosses and stun immune enemies, but SS tree is very good at survivability.
However 2H templar will have a problem since your defense sucks and dps is situational. Not impossible, just difficult, especially in two DLCs.