I think thefox offered some very good suggestions. I would add that one potential problem with personalized frugal dating is that it can be easy to veer too "domestic." Maybe this is just me, but if I'm on a second or third date with a guy, and he's going to cook me dinner at his place, and he takes me grocery shopping with him, my head can go into this weird space, because I'm doing the exact same thing with this brand new guy that I did a million times with a husband or similarly domestic long-term relationship partner.
ETA: Since you are also polyamorous, I think a great idea would be to figure out how to create or cultivate some inexpensive "third spaces" to which you can bring dates, but not all your dates. One kind of weird thing that happened to me when I was first practicing polyamory was that two of the men I was dating decided that they really like this one restaurant near me, so it became an "our place" for me with both of them. I think with solo hub-spoke polyamory (as opposed to polyamory where you are attempting to form a triad), it is better if you have different places you go and different things you do with each of your partners. For example, I got into doing Slow Ride and picnics with one of my partners, I primarily worked on my permaculture project and watched films with another partner, and I frequently traveled on business trips with my third partner.