It depends a lot on your budget and if you have oop healer or do pole parties, etc.
I'm a big fan of heavy+melee weapon for melee and robes+mage weapon for casting.
heavy = fp, robes = divine for more max mp
In partys you'll want something with /focus SA but without -acc since you'll be hitting higher-level mobs. DS/focus sounds cool at first but you'll be doing miss miss miss miss. Unless you're tanking (which you shouldn't since you won't hold aggro well at all), you should use robes in parties to help with buffs, heals or aoe stuff.
In solo you'll want something with /haste sa if you don't have oop healer or /focus if you have a buffer with DW. Daggers can work well in solo since you'll mostly go for whites and sometimes greens.
If you plan to do any pvp you'll need robes + caster weapon.