Organizing a keyset group buy isn't the easiest thing of the world, far from that. Each country have its own standard layout, even between countries sharing the same language (France & French Canada, Portugal & Brazil, Spain & Spanish Latin America, etc).
That affects directly the availability. In a niche market as this, making only the most common layouts is a matter of keeping costs as low as possible. That have a side effect: the uncommon layouts are not supported OR are even more expensive to be acquired.
I've made an empirical study, comparing some of the most common national keyboard layouts (not restraining myself to mechanical keyboards) : United States (ANSI), United Kingdom (ISO), Germany (ISO QWERTZ), France (ISO AZERTY), Italy (ISO), Spain (ISO), Norway (ISO), Sweden/Finland* (ISO) and Brazil (modified ISO, called ABNT2).
*The layouts of these two countries are similar enough to be considered the same. Feel free to correct me.The result is here:
http://www.keyboard-layout-editor.com/#/gists/a3b0575e0b8432a31a28This link shows only the 60% portion of the keyboards, the one that have most differences (numpad differences are negligible and not treated here). The colored keys are those that changes between layouts, the white ones are common to all of them.
All that said, my proposal is this: make all group buys from now on with a mandatory base set (the white keys on the study) and a mandatory national set (the colored keys on the study). That way we reduce the price paid for all users that are buying ISO sets (being honest here: US is
the market for almost anything in the world, it is understandable that ANSI layouts are the standard keysets for this reason), because they would not subsidize keys that they won't use. (Example:
Granite International Keycap Set, $35.99 option at Massdrop containing freaking
86 keycaps when people would use just a handful of them.)
The intention here is to reduce overall costs, but I could be wrong. Opinions are welcome, but let's keep this discussion sane and civilized.