I can fault Wayne for two main things only:
1) trying to run the team like a corporation with the "one voice" approach. This team has needed a traditional structure for years, with a head coach and a separate GM. At least he appears to realize this now, with Cameron being the coach and Mueller being the actual GM and not just a figurehead. Hopefully it remains this way.
2) trying to make a big splash with his coaching hires. I understand the appeal of doing this, but it isn't always the best move. It backfired with Nick Saban, and with Jimmy Johnson to a lesser extent. Saban obviously was at least somewhat wanting to come here and coach, but Wayne is famous for being persuasive and usually getting what he wants, and I think his desire to bring in the biggest name out there caused him to overlook any potential bad aspects of hiring him. Hindsight is always 20/20, and at the time, everyone applauded Saban coming here, but there were warning signs. Also, don't forget that he made an attempt to go get Pete Carroll after Saban left.
Other than those two things, I think Huizenga is an awesome owner. He knows his limitations on football matters and keeps his nose out of things. He never has had any problem spending money, whether it be for coaching or for doing things to improve facilities (yes, including the practice bubble), and overall I see him as a guy who genuinely cares about the franchise and the fans in more than just a "bottom line" business sense. He wants to have a winner.