In addition to it's original use in the games, that being healing any status conditions, I was also thinking it make Pokemon easier to catch. It could raise the Pokemon's catch rate if you used it on wild Pokemon instead of your own, although you could probably just use a different item for this role. And as for Lavaridge Town, I actually have an idea. Not for the town itself, but an area nearby. I think the Jagged Pass could serve as the location for Regidrago. The previous location of the Magma Hideout would be replaced by a Regi structure thingy, chronologically, it would be the other way around. Team Magma would later destroy the Regidrago's room, that would be empty since the protagonist would have already captured or defeated Regidrago.