Yes, the bike will have a tendency to lean if you try to balance on the bashring, although if you ride left foot forward this is far less of an issue. The trick of course is not to use it at all! The ring/plate should be there to protect things in the event of coming into contact with something, and it's always good to avoid using it if you can.
The bashplate is based on what the Megamo's used to run and I don't think anyone makes anything which would be a direct replacement. On mine the rear mounts got pushed up into the chainstays and on one frame resulted in snapping the stay, the other one dented after a few rides at which point I returned the frame to Revell and bought a Zoo Python!