My own important stats (stats other than Intelligence and Charisma) are all 18s currently, without having used any Tomes on myself. I currently have a significantly higher HP than Minsc (11 points over), but that will probably change when I switch to cleric and get only d8 rather than d10 hd, or later +2 rather than +3 hp per level. I'm using myself and Minsc as my frontline fighters, generally side by side, though I use a shield and so have a better AC than Minsc, who dual wields. I'll probably want to give it to Minsc, but if I'm correct about raising a stat of my choice in BG2 I could get my constitution to 20, giving me regeneration.
I plan to use the wisdom tomes on myself, as I'll be the only non multiclassed priest in the party. The dexterity will probably go to either Minsc for a bonus to AC or to Imoen (who I've dual classed to mage after raising her thief skills) for the ranged thac0 and extra +5% to all thieving skills. I'll probably use the strength tome on myself, to get the large bonus at 19 strength.
My question is, is regeneration from Constitution 20 my best option? Is it worth a lower HP Minsc? Am I correct about this stat bonus in BG2 at all? Is Minsc, with his BG2 stats, equal in ability to the new NPCs available there? And are there completely different uses of the tomes available, which are significantly better?
I should probably add that the rest of my party is the canon party: Dynaheir, Khalid, Jahiera, and Imoen. I've disregarded using the tome on Khalid, as I've been using him as a midline ranged fighter primarily, as it's in character for him.