Glad you like the game, and thanks for taking the time to say so! Made my day.
As for the predictability of the solution, I think you may simply be running up against the vagaries of the RNG. It should be randomizing the positions, but just to check on your report, I played a 3-suspect mystery over lunch today, and only the motive was in the first slot in the mind map for that game; the other three aspects were in the second and third slots.
So while it doesn't mean that there's not something else that might be causing it, I wasn't able to reproduce the issue you described on my end. I'll give it a few more goes tonight, just to dig in a little more, but on the surface anyway, it seems to be successfully randomizing the positions.
How many suspects do you use when you play? In a three-suspect game, you'd expect fully a third of the time for the correct element to be first, so it's not super unlikely that the RNG could spit out a stretch of consecutive games with the mind map positions of the solution being fairly similar.