Read Janish's book. Really great for concepts.
My 2 cents on flaked vs malted oats. I used flaked exclusively for about 3 years. I was having some issues with haze stability (yeah yeah, burn me at the stake) but never experienced any oxidation (well over 20 batches). I tried malted oats per Janish, and the haze was great, but the mouthfeel and flavor were a bit off. I can't describe it, but it seemed a bit thin. Flavor seemed to dissipate quickly. Nothing changed with my process, except I swapped malted oats for flaked oats. I did 4 batches with the malted oats and although the haze seemed more stable, the flavor wasn't what I was looking for. I have since switched back to all flaked adjuncts. Equal parts flaked oats and flaked wheat, with a healthy dose of white wheat malt with Rahr 2 row making up the base. Malted oats have taken a back seat in my NEIPA brewing....
Side note - I used to always biotransformation hop (usually day 2) and then 1 DH charge 3 days before kegging. I have since stopped the BT hopping and usually wait until at least day 5 for the 1st charge, and then DH again 24-48 hours before kegging. Janish wrote most extraction happens within 24-48 hours depending on hop type, temperature and mixing. I'm on board with that. I have zero haze issues now, but I still think it's from multiple factors. Type of hops make a HUGE difference. Mosaic is difficult to keep in suspension. Citra is fairly easy. Galaxy and Strata = HAZE. Higher AA AND Beta acids. I've also come to the conclusion that DH closer to the end of fermentation is better for haze stability. Took me a long time to agree to that. But I've done the exbeeriments myself. I make NEIPAs 3 to 1 to any other style. Hope that helps someone!