suggestions

It would be nice not to have to do these seemingly every other match. I get no more then 3 before I have to do another.

You mean you have to do a captcha every 3 fights?

They appear every 15-25 minutes, so if you're getting them every other battle, it probably means a lot of time is passing between your battles. These are unfortunately a necessary anti-cheating measure for now. It's possible they could eventually be removed if other anti-cheating measures were made stronger, but that needs to be thought out a bit more first.