Thanks to the way resource packs work, you can choose the order of preference the game picks them in. You can quite easily set the pack you normally use (eg. Conquest) as the top priority, and let the VC pack fill in the blanks below it. There's nothing to worry about there.
I'd like to stress though that the pack wouldn't change anything. I know some people don't like resource packs, and I don't want them to be excluded by having a pack filled with changes. The only thing the pack would do is add new things. New sounds, new music, new items (kinda). That way, even if you had the VC pack on the top of the list, whatever texture pack you use normally would still be the one deciding all the textures and stuff.