I'm glad the OP brought this up. The lack of Heal potions for pure Barbs and Fighters has been bugging me for a while. In the same vein, I've felt really under-powered in melee on my Pale Master 18/Monk 2. The melee attacks do OK DPS, but I've found myself really outclassed by Barbs. I mean, they've got twice my BAB, and 40 more points of strength when fully raged. How am I supposed to compete with that? It's high time for more potions to be added. At a bare minimum, I'd suggest:
Potion of BAB: Raises BAB to character level, 5 minutes.
Potion of Barbarian Rage: Character enters a killing frenzy, getting a +20 bonus to Strength and Constitution. Character cannot cast spells while Barbarian Rage is active. Duration: 2 minutes
Potion of Being a Warforged: Character gets all Warforged immunities, and may wear Docents as though they were a Warforged. Duration: 10 minutes
Of course, once some of this basic tech is implemented, there should be lots of other applications. For example, I don't really have time to invest in multiple TR's. I'd love to see:
Potion of Past Life <type>: For the next 10 minutes, character gains the benefits as though they had the granted Past Life <type> feat. This potion can stack up to three times.
I'll leave the rest of the possibilities as a exercise for the reader -- I think it's clear how much more fun the game would be if my gameplay wasn't arbitrarily restricted by decisions like "race" and "class" -- this would only make the game more fun for everyone!