simple64 (formerly m64p) uses simple64-gui, a brand new N64 frontend written in Qt6. It supports all of the things you’d expect from a frontend (savestate management, pausing, screenshots, etc.).
simple64 comes bundled with paraLLEl-RDP for graphics, and a heavily modified version of mupen64plus-core. It should give you the best out-of-the-box experience available for N64 gaming.