Hi,
1: yes, PhotonTransformView is a very effective way, but I wanted to show what PlayMaker could do, and is actuall based on the photon demo itself which was doing it like that. That's all. Of course using PhotonTransformView is a lot quicker to setup and more powerful because it gives you all the lerping options, etc etc, so yes go for PhotonTransformView whenever Possible
2: you need to first implement a proper Platform behavior for your Player, which is not easy, then you add the network context on top. When your player is on a platform, then you have a race condition between the synch of the platform and the player, you need to account for this, and maybe ignore the y value of the player sync while on a platform, provided is not jumping... so not an easy thing to achieve by any means. and here PhotonTransformView may be getting in the way because you will have more difficulty to control exactly when and what to sync given this context.
So long story short, you need to find tricks... your Player logic when on a platform or elevator need to be aware of it and stabilize the y value. a Quick trick could be to reset the y position on late Update for your player to be on that platform. and if jumps can occur, detect when the user jumps and do not enforce this floor contact while jumping.
Bye,
Jean