Speaking as a player, I am against that, RP XP is already much better than people think and I make a lot of my XP, if not most, like that. Yes it's long, but RP'ing frquently gives a lot more XP than one would think. I wouldn't want to see people leveling faster than the current rate, specially not in low level place like Vallaki.
I also recall something similar being asked for the the Vallaki Guard specifically since most of them never dungeon and only get XP through DM and RP and it was refused. I later realized that, gaining more level had very little to do with the fun you can have here. You can still do a lot of thing even if you're a low level.
Personally, I don't think any kind of bonus to the RP XP is necessary, but the only I could possibly see is, character above a certain level, RP'ing outside of Barovia getting a little bonus to their RP XP to encourage them leaving Vallaki and Barovia.
Other than that, I wouldn't want to see RP XP getting better than what it currently is because I think it's already pretty good from I experienced and also because I don't think getting level faster is what we're really after here.