@vikisecrets has a point on his point 1, when I tried introducing punks to a friend he initially didn't know how to use it, so I wrote a tutorial
People that are not used to using Hive Keychain and Hive Engine don't understand well how to buy a punk. They don't intuitively get that they need to install the browser extension, log in, and have SWAP.HIVE (instead of HIVE)
But about the open-source thing, I think it would be useful because people would learn how to use Hive Engine. I tried copying your website to add the functionality I wanted but my version sucks because I am not yet good with working with Hive Engine (and I suck ad making design).
I congratulate you on the Punks on Hive because they are truly as decentralized as it can get, but having it open source would allow people to copy and make it better, of course, others could build from scratch, but having a starting point is helpful.