My problem (second to no offline mode) I have is there is really no interface to Google Navigation. You search for a place in any of the bazillion of the Where type apps, or direct navigation to a contact. No favorites, no history, no searching for POIs or any sort of "under one roof" interface. The lack of route options, avoiding tolls, etc.. of course should be on this list.
With that I have a few requirements of a GPS as a frequent traveler, so I created a somewhat easier way of doing things.
The first thing I did was create a bunch of search shortcuts. I couldn't easily find a way to do this in Google Maps vs. the browser, but this is what I came up with.
So I created a bookmark that points to food - Google Maps and named it Food. I then added this bookmark to a Nav folder on my desktop. When you click on it (from home screen), it opens in Google Maps vs. the browser (it'll open in the browser if you click on it in the browser) and will load up "food" results around your location. I did this swapping food for shopping, walmart, airports, etc...
Then I downloaded Car Dock v2 and this app allowed me to create a shortcut in my Nav folder that opens Navigation in search mode. So I can specify "food" in a different location, such as my hotel destination.
I also used the built in shortcut to direct navigation for home and a couple airports by me.
Not sure if anyone else has seen any other ways about going about this, but I would love to have a better front end interface to Google Navigation, much like say a Tomtom does.