I know this is probably an unpopular opinion around here, but I liked the character Wesley, but find Wheaton the person to be somewhat insufferable

So my biggest issue with Wesley was what an elitist douchebag he could be. He would openly disparage non-Starfleet people, in a way that was at least unprofessional, and at worst outright insulting (like the shuttle pilot picking them up for that crash-on-a-deset-planet episode).

And at the same time, he sucked up to the people above him or who could help his career so unabashedly.