Interplanetary Relations & Diplomacy and Science & Technology
When you consider the summit on Interplanetary Relations & Diplomacy, the establishment of off-world and home-world embassies would be extremely important to initiate continued relationships between federation member planets and Starfleet. The topics of nominations and appointments of homeworld Ambassadors to the federation and federation Ambassadors to the home world would be discussed, as well as what form of government and currency (if any) is utilized. Also, the diplomacy of creating safe and peaceful rules and boundaries around interplanetary relationships is paramount to the foundation of a successful SC mission, in addition to the preservation of a strong UFP across multiple federation quadrants.
With the leaps and bounds of innovative technologies of space travel alone in Star Trek canon, an SC summit on Science & Technology would certainly be warranted. As part of SC, the understanding and exchange of interplanetary technologies between the home world, federation members, and Starfleet for a unified transition would be used to level set all parties in mathematics, quantum mechanics, interstellar cartography, medicine, genetics, and more. Once planets attain space travel beyond the speed of light and in doing so, bends the fabric of space-time, it's imperative that an alliance of like-minded species come together to regulate and ensure the stability of the known universe. A SC summit on Science & Technology can facilitate those discussions.