Good thought on posting a pic. The blue Head is not a Ventoris or an Atlantis--I am familiar with both of those. I believe that it is a discount store model, just Head 107.
Lee you are probably correct on the hitting flat verses more loop.
Re serves, I have been using more of a set to launch type serve lately--loading the arm then exploding up.
I have found that it is returned less, and more weakly compared to my flat serve, and it is less work for me--I get a lot of floaters back with it--so I have been transitioning to it as my first serve.