If you can survive as int/dex, then by all means go for it. int/str is weaker, but with more survivability. At 26+ I started liking int/str better because enemies started hitting harder. Especially when bosses started killing me in 1 hit, I started liking 100 health more than the smaller amount of health, damage, crit and dodge that dex eq provided.

Typically the cheapest eq is found at 26, 31 and 36. That's when I upgraded.

If you are done with primary skills, your next passive skill should be 5/5 Damage.