Good fight, I'll take Toney if we're talking him in peak form, otherwise Kessler is capable of pulling off the upset. Kessler is a standup, technically precise out-boxer, but one that doesn't rely so much on lateral movement as spacing and technique to work his game. It's the lateral movers that really gave Toney problems, and while Kessler's jab would certainly trouble Toney and allow him to take a few rounds, Toney's counters, defense, and greater arsenal would see him through to a comfortable decision most likely.
I doubt Kessler would have the higher punch output. Toney had a good workrate, he'd let his punches go in combination. I'm not one for Compubox, but for what it's worth, Toney put up all kinds of impressive stats on Compubox for landing and throwing a lot.