Yeah, you can definitely modify the gas price manually by changing some of the code on MyEtherWallet. I find that the preset gas price changes sometimes when I visit the website and I accidentally over or underpay as well. Some of what you are saying I understand easily, but I'm only a little educated in coding.
Anyways, thanks for this comment. It's helpful to see it in code form. And to answer your question from earlier. I wish I had bought XRP back in 2016, but I think crypto isn't over yet.
RE: Are you overpaying for Ether transactions?