My monitor (a 17" Acer, NOT widescreen) doesn't even 'register' any difference between the display settings ! (Gmail said that might happen for some.)
Also, your example above reminded me: I also don't like the icon-only approach to the various functions, esp. with them all being basic gray. Old Gmail has text buttons ("delete," "archive," etc.) which I prefer.
Kinda makes you wonder just how many Google/Gmail designers wake up every morning with the "change for change's sake" philosophy and take that to work with them !