19 driver of course would be a much higher (taller) ratio and exacerbate whatever issue you have.
+1 on checking floats and catch can (Thought we said already) as I had the exact same issue with a brand new carb only a couple of weeks ago. Although my symptoms were more a long pause in power delivery when getting back on the power and less about a loss of top end power. In my case the needle itself seemed to be catching it’s housing just a slight amount. I exercised it by hand with some WD40 in there, cleaned it with carb cleaner and sent it down the road.