Two distinct writing styles... Which do you use?

In my, so far very short, time as a writer, I have come across two distinct styles of writing.

(I'm sure there are others, but if they don't fall into these two categories, I don't know of them.)

One of the styles largely makes use of the writer's immediate imagination. There's little, if any, forethought, and the writer simply writes as the story appears in their mind.

I started writing my first story this way. It came to me suddenly, unbidden, ready and willing to be transcribed. I write that story as it is told to me by my protagonist and this seems to work for us. In between storytelling sessions, I take the time to investigate and understand the rules of his world and the nuances of the locations, the people, the climate, making careful notes throughout. And then it's back to chronicling his story.

The issue I find with this style of writing is that things are not always revealed in good time. I sometimes learn something new and have to go back and re-work what I have already transcribed as it changes context or wording ever so slightly.

Most significantly, there was a semi-major re-write of the second setting of the story when it occurred to me that it was too similar to the setting in a rather famous set of stories involving a young wizard. Thankfully, my protagonist seems to concur that the events could have happened in this other location!

Because of these issues, the 'simple chaos' of how I receive the story, I am facing many roadblocks when it comes to developing how it is told. I have approximately 40K words transcribed (and copious notes) but I've revised them a couple of times and I haven't finished the re-write of that setting issue yet so the story itself is sort of stagnating. It's a little sad, but I'm not entirely worried as it's a beautiful story (of course, in my own humble opinion!) and it will be told. Eventually.

But this 'struggle' does make me wonder... What would it be like to write with a plan. What would it be like to write knowing, not the details of the story, but the journey those details will need to take, ahead of time. What if I plotted it all out. What if I had a plan?

This is the second style of writing. Writing with a plan. Writing with an outline in mind (or on paper). Knowing the timeline of the story before the details are known... Is a very different style to the one mentioned above.

I think the second story I am writing will follow this. I hope, anyway. It's a much simpler story, in that I'm not creating any new worlds in which my protagonist exists. The rules are known, there are the same rules I follow in my life, and for that, I think that elements of writing this second story will be easier. I just don't know if this style will suit me. I don't know if it will suit the way I tend to hear stories.

Perhaps, the issue I am facing with my first story lies in that the world itself is what complicates matters, not my style of writing, so I may not find it any easier or better when writing my second story as the world is much easier to get to know. Only time will tell.

I think I will attempt to get some understanding of where the second story unfolds, though, before delving into the details, just to see if it helps or works differently for me.... Or, in fact, if it's even a style of writing that I can use!

So, how do you write? Are you a by-the-seat-of-your-pants-er or do you take a more structured approach?