Make Free Shipping, COD, etc more like Weight-Based shipping

OC package comes with several shipping extensions such as weight-based shipping, free shipping, flat-rate shipping, cash on delivery, etc.

Weight-based shipping is pretty good in that one can/must specify the rates for each geo zone for which this shipping option applies.

Unfortunately, the other pre-packaged shipping extensions lack similar logic. They allow application to only one particular geo-zone (or ALL zones). So, if you want to provide free shipping to 2 out of your 5 zones, you are out of luck. Same goes for flat-rate, cash on delivery, etc.

I would suggest that these extensions should be made more flexible and weigh-based-shipping-like. This can be done in 2 stages:
1. Immediately, the zone selection for these extensions should be changed from dropdown to checkboxes, so that shop owners can select any number of geo zones for the method.
2. Hopefully soon in the future, the interfaces of these extensions should resemble that of weight-based shipping, so that configurations for each zone can be saved. e.g. a store owner might want to give free shipping within UK (home zone) for orders over GBP20, and free shipping to EU countries for orders over EUR50, etc

Bit and pieces of this stuff are done by some extensions in the repository. But this is basic functionality and should be part of core, just like weight-based shipping is.

It's not part of the core, but I do have a Multi Flat Rate Shipping extension, that allows you to set multiple Free Shipping, Flat Rate, and/or Per Item shipping rates. I also think it's a bit easier to use than the built-in Weight Based Shipping method.