I swing back and forth with my focus leaning heavily to one side or the other at any given time, and usually with a large quantity of work in between shifts. For example recently:
In 2017 I had just been getting back into drawing after taking a long break through college. So I focused a lot on subject matter rather than style to get back into the swing of things.
But then after a while when I decided I wanted to get back into comics, I shifted my focus back towards style/influences such that I could refine them to a point that I was comfortable starting a lengthy project with.
After finally starting the comic late 2018 though, I started focusing way more on subject matter way more again. The style was in place, so it was more important to me to draw things to an acceptable level of accuracy (details, proportions, perspective, etc.) and continue improving that through the run of the comic.
Now I'm nearing the end of said comic and, while I'm wanting to work on both style and substance between now and starting the next arc, the style side is nagging at me more lol so I've been thinking about doing some proper studies into my influences to refine that some more in the near future.