You basically should get most cross class skills as a WAR.

The 3 absolutely necessary ones (for endgame) are Convalesence, Featherfoot, and Provoke. You honestly won't NEED provoke until very late in the game, but it will be useful before then, particularly if you get dead and someone manages to resurrect you.

Haymaker, Second Wind, Mantra, Awareness, Flash, and Internal Release are all very useful in various situations.

As for point allocation, there isn't a consensus. STR is useful, and VIT is useful, but they have different uses. While you're leveling, i.e. doing quests and low level dungeons STR is better as it helps you kill things more quickly, as well as self heals via bloodbath and Inner Beast. Starting endgame VIT is generally better because your gear will likely not be that great and the 500 HP buffer will help with harder content. Plus it will buff Thrill of Battle. Later is where people tend to disagree. More seem to go VIT though.