I agree with Aia, the idea with maximum AP sounds pretty good.
Would it be possible to set the purpose of the boots in front of Necro gates only for entering Necro? I mean player would still pay the price for their activation (probably heat), but change them from AP booster to Necro teleport. Maybe set some other minimal requitments. But without boots it would be impossible to enter Necro for most of the players, because 1000+ AP is a little bit too much, or so I think.