If you're already making 15k a month, I would say just bootstrap. How much faster do you need to scale? All the YC startups this round got 150k, but you're look

If you're already making 15k a month, I would say just bootstrap. How much faster do you need to scale? All the YC startups this round got 150k, but you're looking at 15k*12=180k a year, that's already more than YC can offer you. If you really need next level funding, then I would think just emailing/tweeting around would easily get you some good responses esp with your story and already proven market for your product.