My advice would be to start out with a set of skills that allow you maximum control over the battle field but in the end, make sure you have maximised all class and weapon abilities to be flexible in adjusting. The more difficult question will be which morphs to take.

For starters, focus on defensive abilities (blur, shadow cloak) and crowd control abilities (bow: poison arrow -> venom arrow, interrupt; arrow spray -> bombard, root; scatter shot -> magnum shot, range - class: aspect of terror -> mass hysteria, fear that will take quite a while to get to; etc.)

Once these are available, start building your damage combos (like stealth -> snipe -> venom arrow -> switch weapon -> ambush -> killers blade) and train the abilities that you need for those. Once you are comfortably set up, start building up the niche skills or situational combos.

Here is my list of must haves.

From Dual Wield:
Whirlwind - Morphed into Steel Tornado

From Bow:
Snipe - Morphed into Focused Aim

From Class skills:
Teleport Strike
Assassins Blade

From Fighters Guild:
Evil Hunter or Camo Hunter