I am not making any judgements, or accusations. In order to give an accurate answer, I needed to understand the problem you are trying to correct.
Changing the priority of UDP packets is not going to gain you anything. The things you describe all deal with inbound packets and not outbound packets.
What you perceive as 'stick stirring' is due to variable packet latencies, more than anything else. We do not employ "lag compensation". Your computer is flying all the planes in your view. The packet updates place the planes in position, your computer flies them to that position.
Now, if the packets come in batches, as opposed to a fix latency between each packet, then you are more likely to see warping or what looks like 'stick stirring' as your computer tries to figure out how to fly the plane to the burst of positional changes it just got.
Packets coming to your computer, are all transmitted with a fixed latency, from the server. In a perfect world, routers would not mess with our packets. Unfortunately, there are a number of ISP's who make use of load balancing schemes, and who also oversell their router capabilities. These ISP's will cause our fixed latencies to become variable.
