The difference is in "fatness" of Fluffy. If you our bag is brand new, and not yet stretched out - boutique fresh. If your bag is vintage but also not very stretched out, then boutique fresh may also be suitable. You are the best person to decide what your handbag needs!
No. Fluffy needs to have wiggle room as most of the Chanel bags are constructed with multiple folds and to stretch out the fold will stretch out your bag over time. When you close up your bag, these folds contract and so the actual interior of your bag is much smaller than what you can see when you open your bag. The space around Fluffy is designed to give space for these folds to comfortable contract.
As of yet, no, because these bags traditionally have great structural integrity so may not require the support of a Fluffy.
Unfortuately we do not offer custom sizes/materials/colors for any of our accessory products.