I have changed the way I store letters... I was using A5 zip wallets but these get quite bulky and also the ends split. So, I decided to go for resealable food bags. These wallets/bags are for those I had yet to reply to.
I bought some ribbon to wrap them up. I don't have enough ribbon for them all.
Today, I wrote a letter on this lined paper.... slightly smaller than A5, from Santoro. I decided to write on both sides, although the back of the lined paper is plain.... sometimes it seems such a waste to leave the back side blank (but I do not always write on the blank side).
Last week, I received a letter on this A4 card, folded into quarters and the top edge cut. There were 8 panes, the first side as a nice handmade card design, and my penfriend wrote on the other 7 panes. I like this idea, sometimes writing on A4 leaves gaps and spaces on the right hand side and could be perceived as such a waste of space (some creative arty types might fill those voids with doodles), but using A5 might be more efficient.