I'm no professional trader, but between those 3 things that you said, the third one is the only part where I agree on it.

For the first one, so you are saying that I will focus more on crypto trading, and will not do anything outside of that, my profits will be constant? Are you sure about that? Do you mean constant is 100% win rate because if that's the case then I don't think that would be healthy for a trader to focus most of his time on trading. I mean we have other things to do outside trading as well. Focusing on trading might increase your chances of getting profit, but it will not guarantee you that you will get profits every time.

For the 2nd one, I'm trading as well (but not that much), and I didn't conduct any market research at all. Why would you conduct a market research if the only thing that I'm trading is Bitcoin, and some coins that are supported in futures trading in Binance. I mean do you need to do market research every time you make trades? I don't think so.

The 3rd one is the one that I will agree with one condition. If you know that you are profiting in trading, then that's the time that you will increase your capital. I mean why increase your capital if you are just a newbie in trading?

Now to answer the question of OP, this is just base on my experience, and coming from an average trader who are earning just enough to pay some bills here. How to maintain profitability in crypto trading? Just learn how to read charts. That's what I'm doing, and so far, I'm profitable with trading. I'm not an expert in crypto trading, and I'm only using 3-4 indicators whenever I'm trading, but it works FOR ME. Take note that what works for me might not work for anyone.