Just like how Fp4 made it a requirement for you to have an identified account to enter guilds. The same should apply to enter towers in addition to a minimum of 10 hours. It's probably a better idea than the one I suggested in the original post.
Edit: In box fort you wasn't able to enter towers without having tag on? So why not do it to all towers this mean instead of scripting a code to disable unidentified accounts from entering towers, they can just disable players with no tag to enter towers since you have to be identified to get recruited into a tag anyways. In addition to the minimum hours suggestion I would say.