Yes, the tholians have 10 transporters, or at least the ones that have web devices do. They have 20 mines.
The school of thought here is that an enemy must slow down to avoid taking damage from a mine, thius somewhat simulating the effects of the web...
Obviously this introduces many other problems, perhaps more than it solves... So this is a feature that needs to be looked at, as it probably will not make it into the final shiplist.
To me, aside from adding weapons or such to the tholian ships, the mines were an interesting choice.
Tholians ships are all equipped with 12 marines. They are special role NT which means not boardable. So you cant capture a tholian ship for obvious reasons, crago ships being the exception. Likewise, Tholians players will not be allowed to capture ships other than freighters if involved in a PvP. Kinda makes sense, ya know?
Well, anyway, this just helps make the tholians feel different than any other race...