I'd guess that in part my opinion would depend on what the map looks like. If there are other neutral areas to expand economy in, then it could become a bit of a land grab. If the map is strictly border area with one hex neutral zones, then econ merely translates into hexes taken unless there are high valued econ hexes. Now, if missions could effect hex econ values that would be sweet. Otherwise if you want to make econ important, you might set up zones that are like supply grids that are linked to planets, asteroids, bases, or other terrain markers, that once you cut off the supply grid in some manner those econ values are removed from the opposition's total econ, but to receive that econ you'd have to capture the center of that suply grid. Otherwise the econ goes unassigned and unused. Perhaps you might also consider Toten's (?) shipping lane idea and integrating it into some econ scheme.
The base portion of the VCs seems fine and pretty standard, but some interesting things could be done with econ other than it being equated with flipping hexes.