As long as your things take priority, it won't override. The only things I can really see it overriding is the Shivan weapon effects, and if you have them flagged in the main table as "player allowed", I don't think they'd be changed. So I'd have the hook into the mediavps.
The reason Inferno R1 doesn't work with the mediavps is because it was made for retail, the reason INFA doesn't work is because it was originally designed for a standalone release but was later changed for a mod release, but Woo didn't want to change all of his own effects so they stayed.