I'm trying out Mythic Game Master Emulator with Dungeon World. I've only done a few sessions of game setup but I'm already very impressed with the GME. I'd love to hear from you if you have thoughts or questions about solo roleplaying in general, Mythic in particular, or even just tabletop roleplaying in general.
If you're interested in hearing it played, I would highly recommend the podcast "Spout Lore". They, in my opinion, are the platonic ideal of how to play a PbtA game, which is to mostly ignore the rules and bang them into a shape that fits the fiction, rather than the other way around. PbtA games are meant to be unbalanced, I think, because fiction tends to favor the protagonists.
I think that's by design, honestly. DW (and all Powered by the Apocalypse games) are effectively just creative storytelling rules with the occasional die roll. You can (and often do) go whole sessions and roll only a couple of times. Its combat rules are virtually non-existent, and it doesn't even have turns, so balance is not only not a concern, but probably impossible. That's because the players will win or lose not by dice rolls, but by where the fiction takes them. If you like a lot of crunchy stats and rules, PbtA is probably not the path you want to go down.