Nice to see it's an active forum!
I wanted to redesign my testimonial, thinking I need someone to change the CSS. I hired someone who did add a CSS , but also added a blockqoute needed to be added in order for this to work.
Further problem is that whenever there is an upgrade, the files are over written. I told him I have additional plugin called "my custom CSS" which would help overcoming the upgrade. He said that it's okay, but even then the "blockqoute" can be added automatically by PHP code, so you would still encounter the problem need to update your file manually after an apgrade, since this is not a CSS thing but a PHP file code change, which I totally get.
I've got the feeling , I somehow got over complicated and this should be much much simpler thing to do.
What you have in mind? How do you keep a design you want, putting it on files and overcome plugin upgrades.