Hey Kevin, I would say personally that serve variation is very important! Sometimes you may see players doing similar serves for quite a bit but normally just against certain players of styles where its helping them. Also there may well be some slight variations innspinnwhich are hard too see sometimes. But most of the time of think it’s always better to mix and vary your serves to keep opponents guessing.
Of course if you find a certain serve or spin they are really finding hard you may then start to use this a bit more, but always good to mix it up and force them into playing different shots from different positions.
