Potions will not replenish but merchants have a lot of potions and each map hosts a lot of merchants.
In this game int is the best offensive stat. not just for mage but for melee as well. Some weapons have 90% of damage as a magical and it based purely on int.
Summoning can make this game really easy and as a mage you probably must go for dualwelding.
Pure mage is not a good idea but some people like doing it standing in a hammock.
