You might have missed it, but I mentioned there will probably be an option added in the future to turn on display names (off by default).
As for other Lemmy clients, I always encourage people to look around and find what works best for you! There are a lot of great apps and what is “best” depends on the person using it.
You will just have to wait until Lemmy officially supports push notifications. It is planned. Anything else is a hack involving polling.