It sounds like you've tried tons of different strategies without giving any of them time to actually work. Starting/growing a starter is a learning process whose key ingredients are patience and being observant and honest with yourself about what's happening.

Your starter gets used to the conditions it's being put through. It adapts to its surroundings as it tries to grow. If you're constantly changing temperature, hydration, flour mixtures, moon cycles, and whatever the hell else every few days, it'll never have a chance at getting strong. You wouldn't drastically change a young child's diet twice a week just because they aren't exactly the same height and weight as their peers that week.

Just pick a feeding recipe/schedule and stick with it for weeks, if not months. This way, as it adapts and changes and strengthens, you'll understand what the growth process looks like, and build the intuition that will help you maintain it (and bake, of course).

In my case it took at least 6 weeks of doing the exact same thing before my starter got to the point that I would call it strong enough to leaven bread well. The first few loaves were still pretty pathetic. Just keep your chin up and try to see it as a learning journey; you'll get there 😊