2) Currently pg_dump is dumping even the default resolvers configuration. As an example if I have not changed default configuration for say sub1, it still dumps all:
I am not sure if we need to dump default resolvers. Would like to know what others think on this.
3) Why in 002_pg_dump.pl we have default resolvers set explicitly?
In 003_pg_dump.pl, default resolvers are not set explicitly, that is the regexp to check the pg_dump generated command for creating subscriptions. This is again connected to your 2nd question.