I do have a Lumiquest Pocket Bounce - which will soften a bit when you are very close. I think I should have bought the Big Bounce to really make a difference.
I also have the new Lastolite mini softbox for battery flashes (EzyBox Hotshoe), but I don't have a bracket for using that on camera.
I do use this softbox on a lightstand with a Canon 550ex as the main light for studio work.
I could also use an umbrealla with the 550ex on a lightstand.
I could bring this along, but that would add a lot of time and effort to the setup, which is not suitable for what I have in mind for the first entry.
In case you have not seen the EzyBox, it is basically a 38cm x 38cm ft softbox with a bracket containing a shoe mount and fitting for a standard light stand.
The following shot of my little darling was done with a 580ex on camera as master and fill, a 550ex in the EzyBox as main and a 420 behind Sarah used to illuminate the background. All controlled by wireless ETTL, so no metering of individual strobes etc. You do need to shoot RAW when doing this to handle the somewhat inconsistent exposure.

Sarah did her own hair for this shoot
So - soft location light is possible even with a flash operated by 4 AA batteries - within limits.
Regards, Michael