Even on the older tokens, there are still risks too, though yeah that the quality of risk can also depend on some other factors like you said there. Exchange partners doesn't really matter I think, I mean there are crap coins that are still listed on a big exchange like for example Binance and then few days later they can still dump hard. After a pre-sale, there are investors on it that will dump their cryptos after it gets listed and that is why the price usually dumps but sometimes it can still recover eventually. Another risk of buying earlier is that the project may not get listed anymore. So I think for me, I'd rather buy late/later but more surer.
Yes, you can consider all of that from the start, and it is a wise choice to first monitor the coins you want after the pre-market, without rushing, it is a process to assess in order to know for the future, I think it is the right step to buy after there is progress or movement, that is important.