Cathode is objectively much better than cool-retro-term, which while cool, is just not nearly as good. I use both. It was well worth my $5 to support the author of this project. Cathode was also first and cool-retro-term is at least arguably a clone. It's great that it's open-source and cross-platform, but I don't find it usable enough for actual work in Linux, whereas I use Cathode all the time on OS X.

Apologies if my wording gave you a wrong idea. What I meant was that Cathode has a good variety of themes and customization features.