Improvement Potential

I consider myself to be fairly smart and a hard worker, I’ve achieved a 4.0 every year since middle school (currently going into junior year). At the beginning of freshmen year, I took a practice ACT and scored a meager 25, and just recently took a practice SAT and scored 1250 (roughly a 26 or 27 ACT score). I did this without any studying whatsoever, but I understand that even with a lot of studying and resources, it’s incredibly hard just to improve 1 or 2 points (ACT scale). I honestly don’t think I’m that stupid, and I know kids who are probably less smart and get lower GPAs (sorry I sound like a total narcissist) that scored far higher in the 28-30 range. I’m blaming my low score on the fact that I’m naturally a pretty poor test-taker, but I’m curious how much approximately I would be able to improve if I studied for around a year (planning on taking the test next spring)?
Should I devote a lot/all of my resources and time to this? Or should I do some test prep and then try and take a harder course load, do more ECs etc?
Any feedback is appreciated
Thank you.

You took the practice ACT a long time ago. I would take another practice ACT, see how you do, and make a decision about which test to prep for. Part of the juggling act of junior year is test prep and test taking. My daughter got a 26 on her first practice ACT (no prep), and ended up getting a 34 on the actual test after she had prepped (which mainly involved weekend work, taking a lot of practice tests and learning from her mistakes, plus working on being able to finish the sections on time, which is a big part of the ACT).

I took the PSAT in 10th grade and received an 1160.
My GPA has never been 4.0, the closest I’ve gotten is one B per semester (I’m in IB though so).
I studied for a combined total of more than 200 hours, without any tutor, for my ACT.
I got my June scores back, and I received a 36.
If you put in the work, you will improve to the level you wish to. You just have to want it enough.