I suppose it depends if you selling flowchart software to mainly technical people? Else if it is more like Excel users, you may want to go with 'as intuitive as Word' or something similiar.

I'd just list 'fully secure' or 'encrypted' as one of the features, and not put it in the price plan at all.

True enough on the Web 3.0 look! I'd recommend using one of the many colour palette tools on the Web though, just to get a more natural softer look between the various hues.