bingo suggested years ago that it would strengthen anakin's character if the chancellor is not depicted as the all out evil bad guy until later on. this coupled with making the dark side seem like the logical choice would stop him looking like a complete eejit aswell.
so what do we need for this to work?
* no mean looking palpatine
* dooku as a rogue jedi to suggest the jedi are the problem
* anakin hearing about the dark side, but NOT the as the big bad, ie NO SITH. uncle palpatine basically suggests he does steroids, not murder kids. this cold be done by revealing palpatine as the knower of the dark side earlier on.
* cutting any obvious links to palpatine and the robed mastermind, and also cutting any parts which suggest he is a bad person.
* some palpatines 'revelation' could be moved to after anakin saves him, to suggest his dark side training has begun, this would be as an alternative to seeing him all old.
possible supporting points
* dooku suggests in the final duel that his agents have infiltrated every level of the republic, thus creating paranoia that there are spies and villains everywhere (paranoia that perhaps WINDU is going to assassinate the CHANCELLOR)
* anakin is really worried about obi-wan going against grevious alone. he even dreams about him dying enstead of padme. the scene where he is blasted by the clones is inserted somewhere before windu goes to make the arrest, and it is really heavily suggested that he has been killed. anakin has a tantrum like in EPII and blames the jedi. angry he confronts windu during the arrest and sides with palpatine. the whole 'dooku's spies' subplot would be strengthened here as we would see cody take the order from Seperatist Robe Man.
* some of the ruminations scenes could be recut to show anakin mourning obi-wan.
this would overall be a combination of nightmarish cutting, and some voice work. anakin's actual TURN would be when he eventually faces obi-wan again, and the audience suddenly realises how wrong he has gone. Palpatine is the bad father leading anakin down the lie, Obi-wan is the good father who brings us the truth. it will all be ambiguous until that point.