My experience with Div II is that stat points are sorta important, but skills are far more important. The one thing to avoid doing is spreading your skill points - 5 skills at level 5 are much less useful than 2 skills at level 8 and one skill at level 9. This is because the skills don't progress in power linearly, they progress by some sort of exponential function. That is, an attack skill at level 5 might do, say, 50 points of damage. That skill at level 9 might do 140 points of damage, instead of the 90 you would expect from a 'linear' progression.
So, each additional point spent in a higher level skill is more valuable than the same point spent in a lower level skill.
Unfortunately, this has the effect of virtually forcing the player to min/max, because doing a "balanced" build like you tried will almost always end up so gimped you can't survive.
Finally, potions and enchantments on your armor can make up for any weak stats you have, once you get the Tower and upgrade your crafters a level or two. Armor and Weapon Sets can also have some really great bonuses that help a lot once you've found and equipped every item in the set.
