There are also PP choices in domestic departures. I keep confusing the names, but PG operates two lounges: one that admits all PG passengers and another that admits PG elites, premium cabin, and I believe PP can get you into the latter too... TG lounge is also open to PP, but probably nothing significantly better in there than the PG ones. Miracle and Coral are also available as PP options—one of them has alcohol, which can be handy since otherwise domestic lounges in Thailand are often dry.