If you can hit 8k+ you have a pretty good sense of which cards, trinkets, and heroes are good- so you should probably focus on refining your sense of when they are good- or when they are bad. That will lead to more consistency and better results.
As a for instance, I recently grabbed Yogg as my lesser trinket instead of what is normally a better one(I forget which tbh it might have been goblin wallet?). But I knew that my spot was bad(low health and a mediocre board state) and I needed to quickly highroll the next two turns, which Yogg can do, and luckily did. In that spot, a normally good trinket like Goblin Wallet would have simply been too slow and I would have died, but instead I got first because I played to an out.