I have just recently finished a double LW hard playthrough with a mage archer combo.
Final stats with gear:
STR 5+3
DEX 15+7
INT 8+3
CON 14+4
SPD 12+5
PER 12+9

DMG 366-730
50% crit

28 AP/Turn
Tenebrium 5+2+2
Armour Specialist 2+1
Body Building 5+1+1
Willpower 5+1+1+1
Marksman 5
Scoundrel 2
Geomancer 2
Witchcraft 2
Leadership 4+1+1
Blacksmithin 3 (+2 with non-combat gear)
Crafting 2+1 (+2 with non-combat gear)
Lorecraft 4+1+1 (could just as well be 0, but I like to know the stats of my enemies)
Glass Cannon
Lone Wolf
Quickdraw
Bully
Stand your Ground (allows my mage to use Earthquake without the drawback)

key spells of the other classes:
Walk in Shadows
Bless
Midnight Oil
Summon Pet
Oath of Destruction
Blind