I never put anything into Resistance. As you mentioned, most other stats will dump a few points in there. As long as you're wearing the right armor for the environment you're in, and have a few of the right consumables for whatever ailment might befall you in the place you're trekking through...you should be fine.
I would argue that absolute best armor in the game can be had immediately after ringing the second bell. Right past the Ceaseless Discharge at the beginning of Demon's Ruins is a big chest with the Gold-Hemmed Robes. Ceaseless won't even attack you until you pick up these items. You don't even have to fight it if you don't want to.
These robes are ridiculously light. The only armor to have better defense against poison, fire, lightning, magic, etc. is Havel's armor. And unless you have Havel's ring or a ridiculously high endurance, you're going to exceed your 50% equip burden wearing his armor.
Until I got past level 100 I almost exclusively wore the gold-hemmed robes. Now I mainly wear Havel's armor. If I'm using a big weapon, I'll usually wear the gold-hemmed skirt with Havel's breastplate and gauntlets.
All of this was a long way to say- screw resistance. Get your resistance through the armor you wear.