ng - wooden set + fighter weapon. Its the only time you will use light armor cos you dont have heavy armor mastery yet and by the time you get it you will only have like 6 more levels to go (no point in changing armor for 1 hour)
D grade Brig/Clan Oath hv + fighter weapon
C grade - you can begin to think about robes, but I think that you should get FP set + fighter weapon
B grade - BW hv + fighter weapon/robes + mage weapon
A grade and up - robes + mage weapon
In other words untill you have a decent buffs you should act as melee with some extra skills (buffs + drain). When you become a useful party buffer switch to robes.
Light armors are the worst way to go. If you have a party get robes for cast speed and mp regen (you won't need pdef). If you don't have a party you will need every single point of pdef you can get hence hv armors.
PS. Don't get blunt fighter weapon. I know you have a stun, but you also get +crit rate buff that gives like +4 crit with blunts. Use duals/daggers to fight and the cheapest non grade blunt you can get for stuns.
Are you kidding me!?!?! XD I went PL set for the +str bonus (+8 str in total with tats) and I used it till A grade. Get focus sa weapons and use soul cry. I was owning cata mobs and don't even need heals. My friends were actually amazed on how I'm killing the mobs @.@
I like light armors coz you can carry more shots. But yes in NG - do that quest in kamael place for the armor set, then use Brig in D grade. A grade, I just simply used my DC robe from my Hierophant and used the adena to get an OE'd focus weapon instead. Because you should be able to get parties in A grade.
In D grade I had robes and a +8 Staff of Life. I also had a levelling buddy so that influenced the way I went.
In A grade I have robes only (I can turn on soul guard if I need to plus steal essence if I get in trouble). However, I have both a nice mage weapon AND an overenchanted bloody orchid with SA.
For S grade, I do have arcana robes but I rarely wear them. They cast slower but are good for Mattk in aoe parties. I also only have mage weapon - no fighter weapon. But who can afford blessed s?? So I still run around in dark crystal (my recommendation due to speed bonus) and a-grade weapons most of the time.
When I started my OL. I had robe sets for ng to b grade. It worked fine with tat's and duals to A grade. That's when I had to buy Heavy and dagger. I tried light first, but I like hunting white to red mobs. Then at A grade I was solo'in more because of small clan and no one wants to group OL.
WC are a party toon, but solo same as OL. Solo'in at high lvl can be done in robes, but you'll need SE or EE for recharges or hunt in pot area. All I can say is have fun with it and charge your setup, if it doesnt match your play style. You'll know before you hit B grade if you like the setup or need to change.
I played my OL till A-Grade in Heavy Armor. First with blunt, then with TSU*SLS+8. I played most times solo. U hit most with blunt...but later i took dual cuz of damage and attack speed.
At A I switched to DC Robe cuz of casting speed. First I kept my duals... but I switched on Flaming Dragon Skull acumen cuz blunt with castspeed is best for OLs. Now in S Grade I still use DC Robe and FDS. Well I'm happy, I don't have AM... on Teon S Shots have horrible prices...