This is quite exciting. Looking forwads @_jims to your mods.
@zeltak I was one of the original posters trying to find a Leader Key alternative on KM. For me, the biggest "challenge" was triggering the leader key with a single modifier keypress. This can be accomplished not with KM but instead with something like BetterTouchTool.
I mean, I'm not sure whether you're asking a rhetorical question. Some people don't know about KM. For others, LeaderKey.app might provide a more slick mechanism.
Following @_jims 's work, I've been using a setup like that. It's not as nice as LeaderKey.app because it requires some manual work setting up, but the work is minimal, and it grants you the overall flexibility and power of KM. LeaderKey also offers the native ability to launch with a single keypress (instead of modifier + key), but as I said, this can be dealt with with BTT.
With the debate between KM vs. other tools, I feel like there are echos of the classic debate of Apple vs. PC. Mac didn't do things that absolutely couldn't be done on PC, but they did it in such a slick and intuitive way. Think of the difference between KM and Window's Autohotkey.
My point is that we shouldn't just dismiss some of these third-party alternatives to KM. The truth is that sometimes, interface and intuitive controls/mods really do help. KM has a very old-school "power tools" view of things. This is why we like it. But it may not have same bells and whistles as alternatives.