That's why I posted it here, some good ideas are coming out.
Putting the bikes in backwards has the handlebars protruding into the area you might want to use when climbing in for other items. Handling the bike from the front wheel or handlebars is a bit cumbersome. An advantage would be that the bike wouldn't lift in a panic stop, and might not need to be secured at the back wheel.
As for moving the base out to load it, that may be an issue if you want the bikes with the trailer attached. With my setup, it is actually easier to allow the bike wheel to rest on the tailgate before getting in and putting it in the final position. I did try moving the base with a PVC pipe under it and that worked reasonably well, but still had to retrieve the pipe.
I could have gotten fancy and designed a self latching device for the front wheel, that could be released by pulling a cord, but I'll try this for a while.
Thanks for the replies keep the ideas coming.