Yeah, I have the same problem. Especially pronounced when I play Morrowind, so I have to monitor myself VERY carefully. To explain, since there are a ton of magical effects, keeping some on hand is not a bad idea. But if you're not a spellcaster...or even if you are, mana can be an issue, you can stockpile potions, scrolls and even enchanted items. Which turns into "let's haul half of my max weight capacity in effects I MAY need". Yeah, to be honest, I don't think a potion of slow fall is that good - I mean, come on, I can count the number of times I was stranded mid-air and needed slow fall or I'd die. The number is 1. And cure poison? Would be good except, I can't remember how many times have I been poisoned, or if I've been poisoned. Cure common disease? They are minor annoyances at best but may develop into more severe thing unless get treated...however, as I'm going back to the towns all the time, and you can get cured in town, it's not an issue. Restore is for when something damages one of your attributes and you are stuck there at the reduced amount until you get cured. It's pretty much the same as common disease, though - it's rare and you can get cured in town. At most, I would get a potion or two of restore strength, just because that determines your max weight and damaging it can root you in place. Or I can carry some strength increasing stuff (Sujamma FTW) which I usually do for the times I find too much loot to carry. And so on and so forth.
I think the Witcher did potions good - you need them to win a fight. I think that has the winning formula - potions are a major influence of the game, not just something you may or may not need and can easily avoid using. You can skip potions in the Witcher but it's much better to not do it. Also, since potions aren't rare, you don't say to yourself "well, I'll just keep this for later, I may need it more" - you just prepare whatever potions you need FOR the purpose of using them.