I would strongly recommend against this. The fact that you can't differenciate between territories on the map gives smaller players an advantage against players with a bigger area. You can always see that someone is chopping away your territory when you are losing points, and most of the time knowing where your opponent is is only a matter of paying attention to your borders. Bigger players usually already have the advantage of intimidation, so encoraging others to attack them this way evens out the playing field. In my opinion makinng this change would male the game less fun.

Tl;dr: this would make it harder for players to attack ones with big areas and I think it would make the game less fun.