You guys probably talk about two different topics.
1. RPG club was never custom like, so as far as I know - no star wars, no custom skins, no extra unecesary additions. Clean.
2. User interface can be changed locally in your system, so what you choose to put there, it is there.
Simply check RPG files where you can find what you need.https://www.rpg-club.com/lineage-2/en/download.html
I suggest you to use clean edKith patch, as it looks most unobtrusive.
I personally use l2 repository patch because of functions.
Back in the days was using Pizza patch.
Base of those mentioned patches can be found on RU forums, so if you guys find it usefull, lets show them some respect and go give them your thanks there.