i have several experiences with low int casters, but gears are quite different (i have improved a lot).
compare them with yours, and you can figure out how good you could.
1. old caster samurai (1-40=melee, 40-71=cast)
weapon: 37 int sword (lvl40-55), 47 int sword (lvl55-71)
armor: 49 int mail (lvl40-71)
charm: 120ee ice XI (lvl40-50), 137ee ice XIII (lvl50-71)
heal: 92ee heal XII (lvl45-71)
result:
did 2-4 mcc
almost never successfull @ well because of short of mana.
but was extremely safe, life never went down lower than mana

2. current caster ninja (1-40=melee, 40-71=cast)
weapon: 43 int sword (lvl40-55), 47 int sword (lvl55-71)
armor: 40 int robe (lvl40-55), 56 int robe (lvl55-71)
charm: 193ee earth XI (lvl40-50), 190ee earth XIII (lvl50-71)
heal: 198ee heal XI (lvl40-55), 163ee wild heal XIV (lvl55-71)
result:
does 5-9 mcc
more than 80% of successful ratio @ well, but i would rather toss plains to my mage weller.
defense is as horrible as mage, i have to care my life frequently.