How much profit we get from our investment is directly proportional to how much Bitcoin we have in our portfolio and so if you're interested in making more profit, there is no two ways about it, you've got to figure out ways to accumulate more Bitcoin, especially when it's bearish.
I get your concept of variation where two variables increased, which means if you buy 1 Bitcoin, you get a full value of Bitcoin and if you buy a half value of Bitcoin, it means you get the same half value but this can be improvise with some other factors of Bitcoin. Like the time for instance, if you buy a half whole of Bitcoin when the price was around $20k and then you buy another whole of Bitcoin at $45k, and now that Bitcoin price is now sitting around $68k, the first Bitcoin you bought would be having $24k profits after you subtract the profit and the second whole Bitcoin you bought will be having a $23k profits, you can see that the first Bitcoin you bought has more profits that the one you bought later, this is why timing is very important when buying Bitcoin.
The advantage is that you don't necessarily have to wait for years before meeting your goal. Those who bought in bulk when it was bearish have probably reached their goal at the current $72k while those who bought a minimal amount even years back when Bitcoin was around $20k will be in profit but wouldn't have a profit anywhere close to someone that starched a good amount of Bitcoin at let's say $40k
Again, as I stated earlier, the timing is very important. The only way you can maximize more profits is when you buy Bitcoin during the bear market, everything is cheap and people dump their coins like they don't need it only to start running accumulating some sats in the bull run.
What I'm saying is that as much as it's important to buy based on our financial capacity, it's also good to put in additional effort to starch more in our portfolio if we are interested in making a good profit from our holdings. Remember that your profit is directly proportional to how much you've starched up in your portfolio.
Not necessary that, if you know that you are not financially big, the best and recommended time to buy Bitcoin is during the bear market, if you have $70k today, you ca only buy a single Bitcoin but in a bear market, you can get lucky and afford 2.5 Bitcoin. Hence, the timing is very important to accumulate Bitcoin.