Configurable options have a radio button that allows an option to be set as the "Default". Packages do not have a way to sort or set a default price, they are simply sorted by shortest to longest term and default to the shortest term.
Add an option to set a pricing on a Package to be the default option. For example.
1 month $5
3 months $12
6 months $20
1 year $30
If 1 year is set as the "default" then the drop down for pricing would maintain the same order, but 1 year would be the default anytime we visit the order form, unless another option is selected or the pricing_id is overridden by linking to it in the URL.
The order manager will need to be updated to observe this default.