What is the best way to play an occultist? Are they front-line fight worthy? Are there good archetypes? What are the better implements?
Personally I find that Occultists are able to fill a wide variety of roles. I have used one as a Necrosummoner, as an arcane caster and as a tank.
Same. There's no one right way. They are front-line worthy but self-buffing is important.
I'd say Transmutation is the most important implement because it enables frontlining with the implement bonus, Legacy Weapon (which gets you Bane, Holy, Planar, etc. on your weapon whenever you need it for a massive damage boost) and has the best boosts out there.
However, that doesn't make it the best implement. I'd say that title goes to Divination.
If you want to go full caster Occultist, you go Evocation/Divination/Illusion.
If you want to go combat Occultist, you go Transmutation/Divination/Abjuration.
If you want to go necromancer, you go Necromancy/Divination/Evocation or Transmutation.
Divination is just too useful.
Anyway, there's no one right way to build an Occultist.
The occultist in the game I'm currently running is very buff-oriented. He also is the one who picks up every random minor magic/alchemical/mundane item given as loot and actually uses it. He COULD be extremely effective on the front lines with his build, but usually he ends up playing more of a support/healer role. Until he got his evocation implement recently, that is. Thing packs some serious power.
There aren't too many archetypes for it yet since it's a newer class, but the ones that exist are pretty good in my opinion.
Which implements you pick will largely depend on what kind of character you want to play. The class is pretty versatile.