Active Site / UI

As you, at the studio, we work with many projects running simultaneously, and we often come across the kind of questions you're asking.

The great thing about DW is that when you place the file (Ctrl Shift U or AutoSave), the correct FTP settings kick in and instantly switch the file panel to the appropriate project.

Now, as to which file you're working on from the code editor, it all depends on how you work and structure your projects :

• hovering over the file tab (which displays the full path)
• comments placed within the file
• Macromind-style interleaving (as discussed in a previous thread) 

I open one document at a time and close it by hitting X on the tab before opening another. 

This avoids any possible confusion about which document is active on my workspace.

To preview in browser, I right-click on open document tab and select Open in Browser.

As far as UI changes go, don't hold your breath.  Dreamweaver is in minimal maintenance status. No new features are planned except essential security & compatibility patches.  Dreamweaver is what it is.