In my opinion Smartauction is already extremely user friendly and easy to navigate. The "new" site with the huge search bar at the top that I will never use and the vertical search parameters on the left side of the page that you have to keep scrolling down to see all the options is way overkill! 

The main thing most of us would like is the ability to search for more than one vehicle at a time. Example: display results for Chevrolet Tahoe + GMC Yukon + Cadillac Escalade all in one search. Then let us select the trim levels we want to see of these separate models, ex. LT, LTZ, Premier in the Tahoe, SLT and Denali in the Yukon, and Platinum and Luxury for the Escalade. That would save us time having to weed out trim levels that we don't have any intention of buying at that time. 

Other ideas would be standardizing the condition report for 3rd party inspectors so there is more uniformity to what constitutes a "light scratch" versus a "heavy scratch". Require higher quality/resolution pictures. Institute some sort of Feedback/Ratings system so we can rate other dealers based on actual condition of vehicle versus represented condition, ease of picking up a purchased vehicle, etc.