I have Azimuth, radius, angle, latitude and longitude. I can create circular sector using polygon but it needs a lot of points and it will be slow to draw. Is there nicer way in GeoServer to do so?
Nope, GeoServer only supports geometries made of straight segments, it does not support curved segments (yet, at least, hopefully one day we'll get funding to do that). The issue is that GeoServer uses JTS to represent geometries, and the JTS library can only represent geometries made of straight segments. So the choice for a future with curves is either to drop JTS and use something else to represent geometries, or improve JTS so that it can represent curved segments.