Inferno transition between cities.

The question is about strengthening Inferno, and how does a portal relate to that? It would be more logical to reconsider the unit setup and their costs. But if you want to know my opinion, it's this: the only downside of Inferno is its weak Gogs and expensive Magogs. If they spawned as often as in a Castle and were just as easy to upgrade, that would be a different story. And secondly, even more importantly, is the inconvenience of the spawning area itself, its frequent blockage, and its scarcity compared to grass.