Thumbkey is a great project for me.
But I think that the issue of creating keyboards and variants should be more controlled perhaps by the creator.
There are so many variants that it can be confusing at times. Who tells me that the Spanish version of Thumbkey that has moved keys over the original version is the correct one or even the original would not be better just adding the necessary diacritics and the ñ. Many may tell me: "Well, you create your variant and that's it," but with that there would only be another variant to confuse a new person who arrives. Perhaps over time a way to modify your keyboards locally could be added and perhaps share them if someone likes it similar to how 8vim does.
But perhaps having every opinion on how the key layout should be in the official version as part of the official application is not the best idea.