If you customize VT, how about you make it a progressive zone? For example, if your guild (or group, if you make it a group zone) progresses and kills named X (probably one before 1 of the port crystals) then a fairy spawns which will flag toons to be able to use a port fairy. This port fairy would be located at the entrance and it would port you to the next level of VT.
The worst part of VT was easily the clearing, and adding a system like this would not only avoid the need for CoTH bot toons but it would also add a custom feel to it.
Also, I would suggest making it a group zone. The beginning could be easier mobs with a named that's doable with a group of people who can do Trakanon, and build it up to mobs that are unbeatable even by our top geared players. This way we have something to look forward to when we gear ourselves up further

In order to keep people from zerging these mobs though, maybe you can bug Striat to code something where if more than 6 PC's are attacking the named then it recieves a significant boost in power.