--- "do you think it's OK that the join order parser takes anything other than a comma as part of the name?"
I am not sure what is the SQL 99 standard for join order. But it does not matter right now. I think fixing the bug is enough currently, making the parser more robust or smarter may be a future ticket.

How does this sounds to you?

BYW, I like your negative test cases:
-- giving the table name when the alias is required
-- giving an undefined name when an alias is required.