I think the team up feature in the game is great for people who don't typically have someone to quest with but may struggle with some of the dungeons. However, there is some flaws to it, the main one being the wait time. I see max level wizards frequent the kiosk by the bazaar, but I seem to never get help when questing in higher worlds like Polaris, Mirage, and Empyrea. I think something that could help get people to help more higher level wizards is to provide more incentives to help out in these higher level worlds, such as increased gold or loot for helping and maybe even crowns. Obviously people may have different ideas on some types of incentives that could be implemented, and getting input from max level wizards who are the ones going to the kiosk will help, but I think it could be a beneficial way to get the team up feature to work for everyone.
I don't think that gold or even crowns is the right way of doing that. I think that if something is considered a longer instance and if you have completed the storyline of the world already, it should count as at least 2 or maybe even 3 helps.
The loot idea could also have issues with that since if someone was looking for a good item they wanted for their lower level character, they could just farm it on their higher level account.
I really respect that you are trying to think about fixing Team Up. I strongly agree with that. I really try to help out people in Dragonspyre and Celestia to help push them through those worlds since those are very difficult. But since there are no incentives, I don't even wanna go near helping in Azteca or Khrysalis (unless I need gold).