mage + decrepit + clay golem would slow down to almost a stop boss unless they use magic, magic attack isn’t affected by slow. that was the best way for me to solo uber. i only used the clay golem at all time TBH
then if you use a conviction polearm on act 2 merc mage would get more useful as well as help a bit the skeleton as it was lowering defence as well, just not as much as resistance.
id use instead beast runeword on a low lvl axe, literally a act 1 normal axe for strength requirement with might merc to buff the skeleton.
and at hi level the mage could actually kill stuff on their own and deal decent damage in hell, usually i would only run skelly/mage and use revive only if i wanted to wow people with mass minion, kill stuff really fast, protect low lvl character like in chaos run in a ocean of minion or do uber, else i could kill everything fast except some boss with only skelly and mage.
revive only lasting X minute and not following me was something that turned me off
my skill lvl tho was over 45, i know with prebuff gear i had 55 mastery, 53 skelly and 52 mage
all in all mage has their use and is a necessity for uber