It appears to me from reading your response to the problem with Mac's text size being too small, that you come across as not giving a hoot about solving the problem. The text is too small... way too small. Come on man, we faithful Mac customers need help.
As far as I know there is literally nothing I can do to change this system-provided NSTextFinder UI (see https://developer.apple.com/documentation/appkit/nstextfinder).
For example, I'm typing this in Safari and its website search UI uses the exact same control size as Textastic.
I would have to implement my own interface from scratch to change that (which I might do in the future to support regular expressions which the system UI cannot do).
And when, WHEN, are you going to implement regular expression search?
Customer support service by UserEcho