Photo gear advice for upcoming road trip out west?

I've been accumulating photo gear advice for a trip in April to the U.S. Southwest; basically the red rock territory.  Unlike many, I want to take the least gear to get the job done.  I don't want to have to make a lot of choices as to which camera to take or which lens to fasten on.  So, here's what I have.  Canon T1i, Sigma 17-70mm lens, 8mm fisheye lens, 70-200 f4 IS lens.  Canon sx230HS camera (14X zoom).  And a Canon SX40HS (35X zoom).  I have been considering (but do not have) a Canon G-series camera, and even thought of trading in some of what I already have for some m4/3rds gear.

So, what to you advise as the bare minimum to take to be able to handle MOST situations (majority of which would be scenics/landscapes).