I think it's safe to say that we as a community should move away from the current TF2Center. I personally think major staff changes should be put into place rather than try to shift to a different website, though. The ammount of effort put into tf2center is huge, and to throw the (seriously impressive) functionality and infrastructure of tf2center away is crazy imo.
Honestly, just get a group of new admins to run the place from a PR standpoint, and have the technically inclined people stay doing work on the website. The "LALALA WE CAN'T HEAR YOU" vibe that I'm getting from the staff is absolutely childish and needs to change if they want their website to stay populated-- especially considering the impending MM update.
Truth is, it would take a considerable amount of time to get a service up and running that could replace tf2center. Sure, there are great pug websites, but they just aren't ready to deal with 500+ people of such varying skill levels.