Sorry to read it is not up to expectations, and my english is unfortunatly not sufficient enough to go into technical to deep for my understanding lacks how to describe properly.
Something that i miss in your post is, i cannot see that you have set intellismooth on the right above for the clients
On wideview.it site i they speak about older simconnect version but if theey lack update,
Which will be their loss, but i can advice you to look seriously at shared cockpit yourcontrol
It is free, from github,
But keep multiplayer active only on the server pc.
I must say i have not encountered the problem you have and my pc at the time high end, with 3090 and 2 3060ti cards run wideview fluent wirh occassional stutter 30fps capped