Really there is no need to start fresh. You should be able to add a x10 free domain. "something.x10.mx", I had to do the exact same thing. "tbint.x10.mx" I made it default, and I could still add a second TLD. 1 x10 free and 2 TLD. You could delete the x10 free, and save the 2 other domains for sub domains from your own tld. You are only allowed 3 hosted domains. Subdomains count as domains.
I wanted off the Ifastnet free services, and the Directadmin control panel is not bad at all, once you get using it. For me 512 MB disk space is all I need.