lol, omg, I went through the same whole process as the OP, and didn't find any really good solution that I could use.
1 - as others have mentioned, I didn't like the "one side clipless, other side platform" because I had to look down to clip in. Some people have said that you can just ride with your foot on the platform and clip in later if the platform isn't up, but with the hard-soled regular mountain bike shoes I wear with hard plastic on the bottom they just slip off the metal platform side so that doesn't work.
2 - I tried the "large platform" pedals, I used the Crank Brothers Acids. (I didn't like crank brothers though). These were probably the closest I could find - if you wanted to casually pedal down to the hardware store they were fine, but if you wanted to ride half an hour they were annoying. My foot never quite got the grip on the pedal that I wanted, and the clip in the middle of the pedal was always kind of digging into your foot - not a big deal at first, but after a while you would start to notice it.
3 - I tried the Winwood Deksters and really hated them. I preferred #2. For one thing, when riding with regular shoes the platform side always ends up down (I suppose you could buy 2 pairs and put them on each side, but -). For another thing my foot also never got a comfortable grip on the pedal - the platform part is not big, it wiggles around under your foot some because of the clip, and it's specifically designed imo to not let your foot grip it to much for fear that you'll accidentally unclip the platform. I didn't like that at all.
4 - switching pedals. One can also just switch pedals, it's not "difficult" but frankly it's easier to just change shoes if you're going to go that far. And changing pedals always made my hands get a bit greasy. I always wished there was a power tool that would quickly undo the pedals so I could put the new ones on.
5 - the one thing that looked promising was the EZY Superior pedals -
http://www.calhouncycle.com/ProductC...idproduct=2075
http://www.calhouncycle.com/ProductC...&idproduct=799
They're designed to make it quick and relatively easy to switch which pedals are on the bike by hand. I was never able to try them though, as they only have an EZY pedal for Shimano SPD pedals, and I prefer Time Roc ATAC's (for a number of reasons, but also because I bike in the winter and they shed things like snow and mud better than spd's).