Agreed - ideally, the save anytime function is what I'd want.
But I would be fine (and it would probably appease others waiting - if this was even an easier option - I don't know if it is) - but the Auto Save spots (when you reach Screen X - auto save, write inventory items to file).
And then later, release an update that allows you to save whenever/where ever.
Again, not even sure if the "Auto Save" function is easier (just seems easier in my head - and that's a scary place). :)