Some of those ideas are good but not many of them can be turned into editing ideas.

Though it might be possible to transfer the saber duel to the palace corridors and the Throne Room.

What if Obi-Wan cuts Maul at the knee (he could even already have robotic legs) that way he could easily become the Cyborg General in the last episode.

He could fall out of a hole in the palace wall and down the waterfall, instead of yet another death pit.

I doubt if even Sith have the power to survive a saber swipe to the abdomen.

Removing the space and land battles are bold moves.

If the Gungans were replaced by non-CGI aliens or removed from the planet entirely the battle could take place in the streets of Theed.

That would mean building models and filming actors and dropping them into the city fighting tanks and droids.

Maybe you could turn the Naboo starfighters into airspeeders and have them weaving between the buildings and shooting droids and tanks from above while dodging Federation fighters.

A massive undertaking but if it could be pulled off it would make for a stronger film.

Anakin left at the temple is an interesting idea too.

Leaving out Yoda from the PT is more of a problem, not unless he is replaced by an actor playing another Jedi and the references to him are somehow diverted.

I can't see how it could be made to work convincingly.