1. I never really noticed a problem with sharpening. Looking at it side-by-side with other projects, maybe it's bit sharp or maybe it's the contrast, but it looks good. The scene you're talking about has really awful color and contrast on the blu-ray and is tough to get looking good.

2. The color has been discussed a million times since the new versions came out. I don't think I've seen it described as too natural, yet, though. I do think that your opinion is probably biased by the more recent home video releases. In Harmy's, it generally looks quite good but there are some shots/scenes that aren't perfect, as the 35mm scans they were based on were not corrected to the print yet. I like the attempt to get it to match the IB tech, but I realize it's not there yet. I also really, really like the moderate color correction of v1.0, and kind of wish we had a version of 2.5 with that color. :)

3. I've read this a few times and can't tell what you're actually suggesting. A way of making the sources blend together better? With some kind of filter or what? I think if you had seen the sources going into it, you'd be pretty surprised at how well they match. One thing that I think could use a little color tweak to bring the sources closer together is where Luke, Obiwan, and the droids are getting out of the speeder at the cantina. But it looks good enough.