As a founder, you don't want tons of small checks because of legal complications (> 99 entities on your cap table) and not a good ROI on your time initially + ongoing. A workaround is bringing in someone to run a syndicate on AngelList or some other bundling, making it their focus vs yours, and condensing to one entity.
The result is, as an individual investor, you can focus on those syndicates. Two benefits are you can spread risk by doing a wide variety of small investments, and while following more experienced individuals.
I've seen that changing a bit recently with the AngelList Roll-up vehicle[0].
It's almost like crowdfunding for seed rounds, but still with $5k - $20k kinda checks. But it helps out a lot with the legal side of things, so you don't need an investment agreement with a dozen different investors.
The result is, as an individual investor, you can focus on those syndicates. Two benefits are you can spread risk by doing a wide variety of small investments, and while following more experienced individuals.