1) In 0.14.7, the page list was sorted by URL, but starting in 0.14.8 it is sorted by title
2) Actually, the "highlight changes" button should not be present if there are no changes.
3) This might be due to the fact that the page is only shown once fully loaded, and not incrementally during load.
4) From 0.14.8, the sidebar scan now button will scan all pages if none are selected.

As you never mentioned scheduled scans, you should also try SiteDelta Highlight which might improve your situation concerning 2) and 3) - just enable the advanced features on the configuration page.