On the other hand, if you want to keep all or some of your characters then you'll be wanting some guidelines. Here are four, the first two of which were mentioned on the previous screen.
Keep the breakpoints in mind. A +2 Barrel won't help a character who has drunk a Black Potion for the same Stat.
Some character classes don't use certain Stats. For example, a Personality boost would be wasted on a Necromancer, unless....
After using all the temporary Stat boosts you still may need to increase a particular Stat just a little bit higher for a particular character to win at a particular Brazier (Test, Contest, etc). You may want to forgo drinking Barrels that yield no immediate benefit.
Finally, different character classes may get different benefits from an increase in the same Stat. For example, a breakpoint increase in the Endurance Stat will give a Knight 5 additional Hit Points and a Cleric only 2. Of course, the Cleric probably needs them more than the Knight, but if you use the Shared Life Spell then you'll get more value by improving the Knight.