#1 and #5 both fell into the "we wish we had time to fix this" bucket - some of the changes that were made between OS 2 and OS 3 would have caused <1.5 releases to crash on the new OS. We didn't want to hold up those fixes. We're planning a 1.5.1 release soon to address stuff like this.
#2 - We tried an interface with both the edit and map/list toggle button, but they ended up pretty small and hard to tap. Until we come up with a better solution, we've given the contexts with location info a different icon in list mode so folks can tell which ones still need info added. (Contexts with location info get a crosshair on their icon.)
#3 - we'd need more info to be sure exactly what's going on. From work with a previous customer, I believe OmniFocus currently uses the first location results it gets back, even if more accurate results become available later on.
Greg's post makes it sound like this is what's going on. The green pin is the location we get back from cell phone triangulation. It's generally the fastest to respond, but is rarely the most accurate.
(In-app directions aren't supported yet, btw - hoping a future OS update makes them possible.)
#4 - hmmm... I'm getting pretty good responsiveness out of my 1st-gen iPhone when I edit a location, even with WiFi off. (Maybe half a second between button tap and keyboard appearance?)
It's possible your UK location is related to the issue - maybe Google lookups are taking longer? In any case, adding an action to my Brighton context to re-test this when I visit later this month. :-)
If you could
send along screenshots and/or more details on the contexts you're having trouble with, that'll help nail this down.