The increase to the 51g-250g weight bracket on international letters feels a bit rude to me. 

They were $7.40 for a long time, jumped to $8.00, now quickly jumping to $9.00 (the under 50g prices were $2.75 > $2.95 and soon to be $3.00). Unfortunately with my business model, this is gonna hurt if I don't change some things, as I often have to post items out that just tip over into what will be the $9 weight bracket while the buyer hasn't quite paid enough postage for it, usually I just send in one package for the sake of ease, but now it will be more attractive to send two <50g letters, which feels wasteful.