With the ability to create beautiful maps, use great looking effects and observe things in a third dimension, D:OS2 has what is takes to be the next great VTT, especially for battle maps. There are just a few things holding it back.

-It needs to be system agnostic.
-The characters on the screen do not need to have their own stats other than movement, weapon range and action points.
-The cursor should always have distance from character, the way it does now in combat mode. Would also be nice to have be able to use the ruler, like in the divinity engine.
-You need more control over initiative order. In general have better control over turn order.
-The GM needs to be able to take control of the players.

There are other things that could make it better, but they could be implemented at a later time (keeping track of hits and conditions, triggering hit graphics on command, better camera functionality LOS indicator and so on) but these are not necessary to get it going. With the above you could use this game rather than Roll20 or Fantasy Grounds. With the number of users they have, this could be very popular with that community.

The way things are now are great for having people make up and play a personalized Divinity 2 game, and everything is very well done. Making great looking maps is fairly easy and a lot of fun. However; if you want to use this to supplement a more classic style RPG, there are just a few things holding it back.