I like that design better. I'd look into a different font to make it stand out a little more. It's definitely a learning process and you will get better as you go. I'd also beef up your bullet points to get a few more keywords in there to see if that helps.
It does take a while to make sales especially when you're in these smaller niches. Now that I'm uploaded 10 a day, I'm noticing most of the time it's 2-3 weeks after uploading that I start making a few sales for that day.
Finally, don't rule out just buying your way out of these first 2 tiers. I think I bought 18 of my first 25. I haven't bought any since but it's a much easier game once you have 100 designs to play with rather than only 10.
Good luck. You will get there.
RE: Just one of my merch shirts.. any feedback is welcome.