Until recently I've ignored Simple Instrument tracks.  Not sure why.  I guess I was just used to working with Split Instrument tracks.
 
Recently I gave it a go and was excited about the feature and how it would "de-clutter" my sessions.  All that excitement came to a screeching halt once I realized I could no longer access MIDI automation for my synths.  It kind of rendered the feature useless for me honestly.  I was so disappointed.  I've seen a few other posts on this and thought I'd bring it back up. 
 
Please, please, implement a way for us to still automate synths when using Simple Instrument tracks. It would change my life...lol.