I would separate the Infinity and Multiverse saga with two six film mini sagas, Spider-Man and X-Men. Spider-Man saga would be the raimi trilogy, the two TASMs, and Venom. X-Men saga would go X-Men, X2, First Class, DOFP, Deadpool, Logan. I feel like watching these before the Multiverse saga pay off as we start to see these characters pop up, and this order gives you the basic X-Men story while skipping all the awful ones. And with them in between, you get a nice break from the main MCU universe.