Good idea, but if the only thing we know is that Luke got his saber back we’re gonna wonder why he doesn’t have his saber.
In Force Awakens, we never see Luke accept the lightsaber. Even in The Last Jedi, we know from watching that Luke throws it and Rey picks it up again to practice with later. Perhaps the saber toss scene is not needed. Rey just holds onto the blue one.
As for the humor, it doesn’t feel right to remove every joke, quip, sight gag, and gesture. The movie should be tonally consistent with moments of levity, not a joyless slog.
I think the saber toss might be needed if you keep the end of TFA as it is. She so desperately stretches the saber towards Luke that it might seem odd to just have her keep it with no explanation. I’d keep the saber toss.
As for jokes, I would personally remove or trim about 13 of them. Poe tooling, BB-8 head smash, milk face, seen your routine, everything you said, tickling Rey (trim), coin shooting, two Finn lines from the fathier chase, iron, Finn’s reaction to BB-8 AT-ST, cowl, big ass door. I think that still leaves most of the fun intact.