I am a complete nobody (and not even part of the community) But I think something like common scams (and strategies of saving money by not falling for both "India scammers" and "Big Evil corporations") would be great.

I like the more personal questions like (your suggestion) “what do you always plurge on beyond reason?”, as well as small tips threads. I'm not American or in the US, so usually the investment part of the personal finance communities is just completely irrelevant to me, thus my preference :)

I think what's important is to have content that helps people become financially literate, no matter where they are starting from. In the US at least, high schools are in the midst of curriculum battles over social issues, so that the basic concepts of financial literacy rarely get covered.

So, some people here might need help figuring out the optimal investment balance in their after-tax portfolios, while others may need help making a basic budget and figuring out how to pay down their student loans. We need to make room for all of those.

If we have the capability to start a Wiki, it should have some basic topics there that most people encounter at one point or another. How loans work, how insurance works, what's the process to buy a car or a house, how to budget to pay off high interest debt. A lot of this advice is region-specific.

Not memes. Anything but memes.

One thing to note is on Reddit you're used to looking at lots of disparate granular communities e.g. /r/finance, /r/FIRE, /r/personalfinance, /r/povertyfinance, /r/wallstreetbets, /r/stocks, meme subs like /r/pfjerk... While this community is small, we can be all of those things. You start general and then as the niche groups find the content they want to see or is most relevant to them is getting drowned out, they can splinter off. This is why most of what I've been posting is more in line with the historical content on /r/stocks rather than /r/personalfinance. There is some cross-talk, but /r/personalfinance is mostly questions about individual financial situations as well as a repository of FAQs. We don't have a wiki, so the latter is essentially impossible unless we just make huge posts and pin them (which is still worth considering), and with only a couple hundred members the former is not a viable content model.

I want to learn how the world of finance works under the hood

I think a community like this should have two goals:

1. Be on the fairly cutting edge of personal finance topics like saavy tips for current credit cards, tax codes, retirement plans, and retail promotions that help people maximize their money and plan for futures.

2. Maintain resources for basic financial literacy. IMO these are best done as sidebar items since they don't change much day to day, but they are critical for bringing in new members and frankly helping people since most schools don't do it.

I do think part of #2 is letting people ask dumb questions (What do I do now?), but only if their situation is not obviously covered in the sidebar. As sidebar grows, these should become less frequent.