I'm applying to the same program! Good luck!!
I think you'll have better luck reaching out to HCI grads on the reddit.com/r/userexperience/ subreddit than this one. I haven't seen many MFA people around these forums. Recently, I connected with one of this year's students at the MHCI+D program at UW over reddit and it was really good to hear about their background and what they thought helped them get in.
From a general point of view, I don't think it's a problem that you don't have much design experience. As someone coming from a non-design background, I know exactly how difficult it is to get your foot through the door with IxD type stuff. However, by the end of the essay it seemed like it wasn't 100% clear what motivated you to become a designer. (You want to work as a designer after graduation right?) You mention that the program can help you succeed, but I wasn't sure what you wanted to succeed in.
For example, you mentioned both HCI and design research in your work. I'm fairly sure these are not interchangeable subjects, and design research is fairly broad topic. If you can describe a bit more how these different areas related to design will help you succeed in ____ after graduation, I think that might make your essay stronger.