Obligatory sorry for the wall of text :)

I'll preface this by saying I'm hardly an expert in the space, having dabbled with PbtA (Avatar Legends), FitD (BitD) and Mythic GME (all topics I think are related to Ironsworn in some way). I do play Ironsworn: Starforged solo, and have been very thoroughly impressed for the most part. There is definitely an adjustment period, which I think boils down to a few points for me:

1. I tended to view ttrpg rules as more of an ironclad "this is how it works, do not deviate from RAW", and that is something that I feel less crunchy games tend to challenge. There are multiple ways to handle a given situation, and which you will choose will largely come down to personal preference
2. I found it difficult to read the book because it was so full of cool, inspiring ideas that it made me want to play ASAP. So anytime something said it was an optional rule, I would often skip it, only to kick myself later for realising it was the perfect solution for some situation I felt the rules were otherwise lacking for (e.g. scenes and non-combat encounters). I also didn't fully read through a lot of the moves until I had half a dozen sessions under my belt, and things started to flow smoother for me after having done so.
3. I find even now I often forget to use the oracles as much as I feel I should be. At first I viewed them as more of a "this is how I generate a planet, or a settlement". I realise now the core oracles that are more generic are super useful, and I try to ask myself when playing "Do I really like this idea of what happens next, or is it boring to me?". If it's boring, the core oracles can usually inspire me to come up with something much cooler.

Overall though I love playing Starforged solo, and I feel that it has really improved the pathfinder game I'm running right now as well. I'd highly recommend any GM or player to mess around with systems like this that really push you into a different way of thinking, and for other forever GM's out there it's a great way to get to be a player. I also hope to try out the co-op rules at some point with my current group when someone can't make it to a session (instead of cancelling)