Just have a static 100 BASE vitality during your runs with the crap / mediocre gear you have if(IF) SOLO'ing.
Once you have that sorted out, your gear choices will develop with what you know:
Enhanced Effect = Best Option for Weapon / Armor &/or Cast/Heal charm (Main / ACC)
Stat Main Charm if you are Melee and EE ACC slot (these can actually be switched [don't listen to this if you have great gear])
Following is some real fucked up advice that makes sense.
#1: Padded Robes (or normal) are the ONLY choice to buy to complete LS from Feeder to Alchemist.
... #1 (a) ... +X Intelligence is Priority, expect to pay a fortune for these.
... #1 (b) ... +X Dexterity is priority, expect to pay a fortune for these.
... #1 (c) ... +X Strength is ONLY a priority for the first 3 classes and are cheaper (can help when passing to use a Melee Ninja)
Thats' all it is, build around those items... your weapons, main charms and cast/heal charms.