"Half vampire, half lycan, but STRONGER than both."
For those who don't understand how Michael wasn't actually STRONGER than Viktor, remember that when the Lycan medic was explaining their plan, he said the plan was to use the blood of an ELDER VAMPIRE like Amelia or Viktor, which when combined with the blood of an ancient werewolf like Lucian, would've made the hybrid "stronger than both."
They never injected Michael with Amelia's blood. He had to settle for Selene's bite, so while he was strong enough to go blow for blow with Viktor for a while, he was never what he was originally supposed to be.
For the franchise, Michael couldn't end up being far superior to Selene, which he would've been had he become that super-hybrid, so there's no way the writers were going to make him that. Would've made more sense for the franchise to become Scott Speedman's then, which they weren't going to do, lol.
All we ever see of stars are their old photographs. - Dr. Manhattan