Is it code-compliant and safe to add 2 single pole breakers for 15A GFCI and 30A RV hook up circuits to this service disconnect panel? I opened the panel and pulled wires in expecting separate ground and neutral busses. When i realized ground and neutral were tied together on a single bus i stopped.

The double pole breaker is for a mini-split HVAC system installed before i bought the house. I am going to replace the romex with THHN for the 20A GFCI.
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