Your points which you explained about investing in Bitcoin are really on target. You do not need to have good amount of money or expertise to get started. Strategies like DCA in which you invest small regular amounts and reduce risk. Most important thing is to be patient and disciplined sticking to long term plan except trying to predict market ups and downs. Learning about how to keep your investments safe and having emergency fund are crucial for successful long term strategy. And investing well in Bitcoin is less about insider information and more about having good financial habits long term view and willingness to learn.
I'm also of the opinion that strategies are probably not most important but helpful when setting up a good Bitcoin portfolio. Investors with large capital should buy large fractions while investors with small capital can invest with what they have available and accumulate over longer period. Both large scale and small scale investors can DCA, the only difference is in how much fractions can be accumulated over the same period.
OP made helpful points, one thing is understanding Bitcoin, having the capital and securing the investment throughout the process of holding before profit taking. Altcoins are not the best place to spend our capital, especially the new altcoins that lack utility and wouldn't reserve their spot for the long run, instead investors should prioritize Bitcoin investment.