loosening strings
I really don't understand the rationale behind loosening your strings...
Personally I would think that if you were actually playing the instrument (for say 10 years) you'd never loosen the strings right? So if you're just gunna look at it (for say 10 years), why would you loosen the strings? I do know that loosening the strings has an adverse reaction on the bow of the neck, which is adjusted to accommodate the strings tension. If you loosen your strings for a long period of time, your neck will certainly change shape.
I'd love to know why someone would recommend loosening the strings.
Put those desiccant things in your case to absorb excess moisture prevent the growth of mold.