Hi Susan. For a moment I was trying to figure out what was your point lol...but I have been aware of and working around these rates for years so they have not been an issue for me.
First off, whenever you have anything that falls within 200-250 grams, it's always cheaper to use small packet or light packet. The much higher letter rate (if the dimensions qualify) covers envelopes from 200-500 grams so you'd be paying for extra weight allowance you don't need.
Secondly, small packet is almost always cheaper internationally than is light packet. There used to be one international rate for small packet but now it goes by zones so the small packet rate varies. The more advantageous small packet rate (with insurance) vs light packet has been that way since the last two annual increases. It doesn't make sense but just like you, I am not complaining.
It would be nice if Canada Post would break down the last 300 grams of letter-mail into smaller increments for us so that we could send say a 300 gram envelope at a cost that's more relative to the 250 gram rate. They did break it down for Canadian shipments this year but didn't give us any break, keeping the 200-500 gram rate for 200-300 gram envelopes and INCREASING the rate for 300-400 grams AND 400-500 grams. Likewise, it would be nice if they came out with a 750 gram rate that would cost less than the 501-1000 gram weight, but I think we'd all be dreaming in technicolor to expect Canada Post to make changes that would actually cost us less. It seems every year they are looking at ways of changing the postal system so that it costs more for us (like the proposed flexibility rule they did away with last year). My concern is when is enough going to be enough? The rates go up each and every year. Small increases don't hurt but added up over a 5-10 year span, they are enormous. One day it's going to cost as much to send a 500 gram envelope to the US as it does now to send a 1000 gram one.
As sellers it's important to be on top of the ins and outs of the postal rates. I had a lady in Alberta charging me $11 for an envelope that would at the time, have cost about $6 to send if broken up into two separate envelopes. I had another lady in N.S. that wasn't using the online labels with the 25% discount. There are a lots of little tricks and its in our best interest to know them and use them to our advantage. 😉
Cheers!