The OP doesn't seem to regret every dip, but just looks like he's really excited to wait for a deeper drop before making a purchase. There were many people expecting bitcoin down to $25k, but it never happened as the market continued to show recovery after dropping around $25.8k.
Some seemed to regret their decision because the price never dropped to the area they expected, so a change of plans is very possible especially when bitcoin is starting to show something positive. OP just needs to take advantage of dips to buy instead of expecting too deep a dip, even if he has doubts then DCA is recommended for him.
Waiting for a deeper decline will miss the opportunity for the OP to buy as the price is again showing a gradual recovery although a small correction is still taking place in the market now and going forward. One way he can do it is like the suggestion you gave by using DCA and if there is indeed a decline for the next month, he can take the second option by making large purchases according to his wishes and the targets he expects.
Doubt will only prevent OP from buying because he is too worried about waiting for the right conditions to buy, even though under any circumstances he can adjust to the DCA pattern and doesn't have to wait for such a sharp decline to buy. If there are too many considerations in the decision then unfortunately he will not have a chance to see the halving in the next period and lose the opportunity to make a big profit in the next ATH.
I think that short-term transactions, are already trading, if you buy bitcoin for several weeks, or months, and then sell it, then these are definitely short/middle-term transactions. By the way, long-term investments also require you to understand the market, you cannot buy bitcoin at any time and expect to make a big profit, even if it is a matter of several years. If you had bought bitcoin in April 2021 at 60k, then even more than two years later, your investment would still be at a significant loss, so the time and price of the purchase is very important for investing.
What are you worried about when you implement long-term investment in bitcoin, do you know how bitcoin can survive in chaotic economic conditions when Covid-19 takes place and what happens in the following year that bitcoin reaches its highest price. You don't need to understand market conditions for long-term investment, buy and hold bitcoin it will bring you big profits. Cases of loss to investment in bitcoin because it acts on panic and the simple formula is enough to be calm and hold on to the bitcoin that you have, there is no loss to investing in bitcoin if you have made the right investment.
For me when we apply bitcoin investment in the long term you can buy bitcoin at any price like now, because what you have to understand is the long term concept of not being active in trading but waiting for the next ATH. That is why bitcoin is considered the best investment for the long term, besides being able to maintain the value of bitcoin it is also able to provide a sense of security for the assets that you store in the long term.