Howdy there Hoit. There's not much I'd change to be honest. For what it is and what it can do, the Revo is pretty much spot on I think. Its just that the adventure does wind and chop better, and I'm experiencing lots of that up here. If I was still in Vic I think I'd just stick with the Revo.  
 
That said, there is a few things I'd change on all Hobie kayaks. One would be coming up with a seat that has a bit more padding (astro would cheer for that one) as well as a customizable, compartmentalized pockets for the back of it. If I had access to the right kind of sewing machine, I'd have my fillet knife and lip grippers attached to the back. Oh yeah, I'd prefer to see the seat attach to the kayak with velcro to, instead of those plastic lugs.  
 
I'd also like to see the seats and mirage drive a little further back, but i know this would come at the cost of rear storage.  
 
Other things I'd like to see would be accessories, such as gear bags that fit into the 8" circular hatches much like the tackle trays do.  
 
A dedicated lighting system wouldn't go astray ether, but now I'm getting fussy :-)