There lies the rub.

In the ideal situation his aging would progress from what we already see happen between TPM and AOTC.

For no reason that makes sense to me at the beginning of ROTS he appears to have rejuvenated since the last film and then comes the most stupid dumbass shoe-horned special effects sequence of the whole PT.

Lucas thinks his audience so stupid that they couldn't figure out that the man running the show in Episode 3 has deteriorated to become the wrinkled thing in Episode 6 so we have that awful Force lightning reflux thing.

This leads to Palpatine looking like a weird Halloween mask version of his ROTJ self for the rest of the film and there is nothing (even Ady) can do to reverse this totally without cutting the footage altogether.

So whats to do?

For me the only option that works is that Palpatine has a Sidious face and when Sidious is out and about it takes over his body.

Think Pazuzu in The Exorcist.

That way his evil face can just snap into place without the need of that awful CGI transformation which makes no sense because nether Anakin, Luke or Mace melt when they get the full blast of Force lightning in their face.

Yoda and Palpatine should never use lightsabers.

Team Ady have the skills to have Yoda push people and objects around.

They also have the skill to have Palpatine dodge Mace and zap him without the saber.

Dooku should never use Force lightning.