I moved to shopify a little over a year ago. While 90% of it is great, there are just a few things that still do not make sense to me. The default package size is one of them. Is shopify ever going to change this? This is like 10 years old style rules. With how much people shop online, how is it that you only get to choose ONE size at checkout?
And no, there are no apps out there that fix this. Shopify gives you really good rates that we should be able to get correct prices on if they allowed you to change sizes. Would be even great if you could have an unlimited number of box sizes and then assign products to that. Then have rules when multiple items are included what size should be used to calculate rates. Rediculous this has not been solved. Seen many posts over the years and nothing has been done.