Can I make one base soil mix for most houseplants?

A base mix is fine. I keep potting soil, bark, and perlite or pumice as the core. For aroids, I go chunkier with bark. For succulents and jade, I add more mineral material and less organic stuff.

Your watering habits matter as much as ingredients. If you tend to overwater, make the mix airier. If your home is dry and you forget to water, a super chunky mix may make you miserable.

Use vermiculite lightly if you get it. It holds moisture. That can be useful for seedlings or thirsty plants, but it is not what I would add to a ZZ or snake plant mix.

Worm castings are nice, but they are not magic dust. A small amount is plenty. Too much can make the mix heavier than you wanted.

You do not need every amendment on the internet. I grew pothos in regular potting mix with extra perlite for years. Start simple, then change when a plant gives you a reason.

Pumice is worth it if you can find it locally. It does not float to the top like perlite and it adds weight for plants that tip over. I still use perlite too because it is cheap.

Write the mix on a piece of tape under the pot or in your notes. Six months later you will not remember what you used, and that is when the notes pay off.