NEAR strategy around node client(s)?

Qs about clients:

1. Are there protocol implementations other than the nearcore reference?

2. Does NEAR have a goal for there to be multiple implementations (to promote diversity, security, robustness etc.)?

3. Is the Nomicon spec complete (i.e. alone sufficient to specify a client) or are there some dependencies on the nearcore implementation?

Thanks!

FYI: Bowen answered this April 17 over on Zulip:

1. No

2. Yes but this is more of a long term goal. It is hard to do when the protocol is still rapidly changing

3. Unfortunately no