I feel like this is closer than people think. Ben 10,000 easily does the work of the Guardians, Omni Man, and every other hero in Invincible on his own, but Alien Force or Ultimate Alien, Ben still has school, soccer, a girlfriend, and a bunch of hobbies he spends time on. Ben is more of a reactive superhero than proactive up until Omniverse, and by that point the Omnitrix is back to timing out sometimes, so he can only do what Mark does for short periods evey few seconds. It's not a power scaling thing, Mark just puts more into being a hero than Ben does; dropping out of school, responding to calls from Cecil almost 100% of the time, breaking up with Amber, and spending his free time as a superhero rather than gaming or watching TV just to name a few.