IIRC in the original game, the "Recovery" enchantment simply didn't work. I have an idea that some of the mods attempted to correct this and other flaws, but I don't know how successful they were. I do know that some of the glitches were corrected, notably in Mok's and Grayface's patches, but I don't have the precise details.
I disagree with the game's valuation of the different enchantments. My valuation is based on their usefulness in the game, and I found the most useful enchantments to be "of the Dragon", "of Darkness", "of Power", "of Protection", "of Plenty" and "of the Phoenix". In the next tier are the enchantments that couple regeneration of either mana or hit points with another benefit, and the "of x magic" rings.
My biggest disagreement is with the game's high valuation of the "of the GODS!" enchantment. These items would be sheer gold to a low level character. However, the problem is that your party does not start to find these until the game is fairly well advanced, and your characters are pretty competent, with prime stats well up towards the 50+ region. At this point, "of the GODS!" items add at most 1 point (and more probably nothing) to the abilities governed by your prime stats. I won't go so far as to say they're useless, but they don't materially boost a character's performance and IMO their main value is in what they bring in when you sell them.