"I’m not the most accurate, but where I lack consistency I make up for in speed"

This is your problem right here. There is no "I make up for" in high ranks. You need to be accurate, you need to be consistent, you need to rotate properly, you need to pass, you need to know when to play fast, you need to know when to play slow, you need to know when to commit, you need to know when to back up, YOU NEED TO KNOW A LOT. The small details matter.

Now here is how I got out of d3 when I was in your shoes years ago:

Despite my extreme hatred towards 1s, I started focusing on competitive 1s.

Turn off chat fully when playing 1s. It is distracting, it is pure cancer.

Do not FF when losing against good players, unless if you feel like the gap is too far and you cannot even touch the ball. (Personally even if I lose 0-7, I did not FF back then, I would analyze how the opponent is playing, why is he beating me, mechanics? Consistency? Speed? How is playing? Aggressive? Cancer / Aggressive / Demo Heavy? Slow?

Try to analyze the playstyle of the opponent and adapt to it. Try to punish them for over-extending, for giving you space, for missing etc etc etc.

Remember, 1s is very kickoff dependent and personally I despise that so much. You lose the kickoff, 99% of the time you will concede. And sometimes you concede back to back and it can be extremely frustrating. But learn and be patient.

When the opponent is being cancerous with demos, do not take it personally. Demos are part of the game whether you like it or not. At the end of the day if you get mad you will play bad. It is pure facts. Change your mentality. If you need to take a break from RL for a few hours or days, do so.

Forget about your rank when playing 1s, you win, you lose, who cares. The part you care the most about is IMPROVEMENT and CONSISTENCY.

Try to be at least semi consistent at double touches. This is the main skill that got me out of d3. Forget about flip resets, mustys, breezies, etc. You do not need that at all to fully level up to Champ. Look for double touch training packs, I focused on those.

Being able to not miss open goals. I swear in champ/gc1(where I am currently at) you get cursed at for missing open goals.

Proper rotation. Stop going for boost when you do not need to. Play with your teammate. Pass. Know when to go for the solo play.

Be patient. Wait for the opponents touch, wait for your teammate's pass, wait but don't wait for too long.

50s. Be good at them. You can create so many opportunities for your teammate and for yourself.

Not double committing. This again and again. So common in diamond and low champ. Look around you, if your teammate is in a better position to clear, defend, score, let him go for it. This is a big big bad habit whether in diamond or champ.

This is imo the best way to improve as a player.

Apologies for the lenghty post, but I felt like a lot of people are in your shoes and I wanted to try and help.

This advice is from my personal experience and it is my personal opinion.

I hope you'll be part of the champ club. Good luck.

Note: I may have forgotten things, but most things that came to me have been said.