Making Jango Boba could work too. I don't really mind young Boba though. I think Lucas showed just enough of him for us to figure out what will happen with him (the shot of him picking up his father's helmet at the end of the arena battle says it all) without showing everything. It's also a nice little touch we now know what Boba looks like under the helmet in the OT, without having to see it. We know he is a clone, and with seeing Jango, we'll have a good idea of what Boba looks like in the OT.

As for Jango arresting Anakin and Padme, and omitting the droidfactory sounds like a good idea too. Personally, I like the droidfactory scene, but I think we can't have both the droidfactory and Padme's conversation with Dooku. It would destroy the momentum of the movie.

I think both scenes are good and I could go with any of them, but personally, I like the droidfactory a little better. It's fun, but also helps the pacing of the movie in the end a lot.

But the scene with Dooku and Padme is still pretty good: there are some great lines in there, it's nice to see a bit more of Dooku, and finally see the two opposing sides in the war sitting down and talking face to face. I don't think that happens anywhere else in the PT.