If you rework the Town Portal, you won't have to spend the whole game defending resource locations and building chains of structures for various purposes. For me, this would diminish a part of the game, although it might be beneficial for offline tournaments with strict time limits.
You could make it twice as expensive, but I think that's too costly. And you still need to be able to build Archmages somehow.)
It's bad when, due to a lack of control, a player spends time gathering resources instead of fighting.
And the observation about offline tournaments is absolutely accurate!)

