This right here. We've spoken to many dozens of Angel, Seed, and later-Stage investors. Principals and Associates are market researchers, not investors. If you're interested in being part of uncompensated market research and you have time on your hands, then take their meetings. If you're trying to raise money? Take meetings with General Partners or Managing Partners, and if you can't do that, then figure out how to do that. It's also very good practice for figuring out how to navigate the political, social, and marketplace incentives of a weird unresponsive system if your business happens to also be positioned to sell to "enterprise", but I digress.
Insofar as identifying great investors that a founder should treat as more than a check in the bank, I've learned through scar tissue that there's a very good qualifying criteria. Every VC talks a lot about being part of the team and how much they'll help you. The great ones don't bother with all the talk. They just start helping.
The Seed-stage ecosystem is also a really weird one. There's a lot of "tech celebrity" investing that distorts the lens of how the machine really works for everyone else, what's misaligned between how Seed is positioned vs. what Seed funds can actually do based on their constraints and incentives. It was quite the learning process for me and my co-founder.