A 1st lvl psywar can have the Psionic Weapon (or Psionic Shot) feat, giving it +2d6 damage to one attack per combat, for an unlimited number of times per day (as long as the character has at least 1 PP remaining).
At 5th lvl, a psywar can have the above plus the Psionic Meditation feat, allowing it to use that extra 2d6 damage once per round, providing that the character can make the DC 20 Concentration check.
at 8th lvl, a psywar can have the above plus Greater Psionic Weapon/Shot and the 2nd lvl power Hustle, giving the character an extra 4d6 damage with one attack per round... while making a full attack.
Aside from using Hustle to get a full attack and a move action in the same round, none of the above requires any expenditure of power points. The psywar need only have 1 PP in reserve so that it can regain psionic focus (and be able to make high DC Concentration checks).
Aside from that, Vigor gives you a LOT of temporary HP for your power points, Hostile Empathic Transfer is pretty deadly in the hands of a psywar, and Force Screen allows you to wield a greatsword and still have a decent AC.