It depends on your use case. Makie makes it incredibly easy to make beautiful figures for scientific manuscripts, which is my use case. Getting the same thing with ggplot or matplotlib is a nightmare. But I digress…
You’re in highschool, making cool shit as a hobby, you’ve already taught yourself (at least) two languages, and you’re using them to make stuff you want to make. Awesome! You have preferences about start up time vs execution time, which is a trade-off when choosing your language - that’s also great. It’s important to know your own mind. Given where you are and what you want, Python makes sense.
Many of us have different needs, and the few seconds or even minutes of start up pale in comparison to differences of hours or days in running our code. Different uses, different trade offs, different priorities. All of this is fine.
But I’d like you to consider how this post comes across. I’m certain this wasn’t your intention, but you’re basically saying “this thing you all use is good, but if you put more effort into the things I care about, it would be better.” And nothing in your initial post is really actionable - TTFX is a known problem and heroic efforts have been and are being made to improve it. We cannot magic a larger community into existence - the difference in age between python and julia is larger than the time you’ve been alive, AND python has had a number of large companies that have poured money into it. Julia dev has had a comparatively shoestring budget. Your notes about visual defaults really come down to personal preference, and more polish requires lots of time and effort. See this thread for a bit more on these points
I totally get it. When you’re a fan of something, it makes sense to gripe about the things that aren’t perfect (incidentally, we have gripes channels on slack and zulilp - come join us there!). And at the same time, coming here and writing a long post about the ways you prefer python, when none of your complaints are readily addressable might bum people out. But given what you’ve already managed to do with yourself, I suspect you CAN make a difference. There are many ways you could turn your energy towards improving the language or the ecosystem, and in the long run, they might be more meaningful than some cool visualizations 
.