I really like the idea but I don't think it would be able to be implemented just because Bedrock supports crossplatform. For example, it would be far far easier for someone on Windows 10 to kill someone that is on mobile or console. With the leaderboards being implemented I can't see any mobile players being on there. What I'm trying to say is that mobile players suffer from a big disadvantage and that is the control system.
IF they found a way to make the PvP servers platform exclusive (mobile/console/win10 only) then I would be all for it but at the moment it would just be too impractical to implement. Maybe in the future tho