Merry Christmas Slicepong!
Wow that’s great, table tennis at a Christmas party sounds amazing. Ok so firstly with the balls with no pace, the best way is to try to firstly get into a good position and play a topspin shot, as you mentioned by coiling the arm and getting a decent backswing, and making sure to go for spin but with a good acceleration. Also as you said pick a target and stick to it, be decisive and go for a specific spot or area on the table.
For the long fast serves, it’s very difficult to push them back and have control doing that. Again the best way is to topspin, with these you need a shorter stroke and to try to guide the ball back to keep control by going for a good brushing contact and not hitting too flat which can cause mistakes. If your still struggling really focus on returning more towards the middle of the table and being careful not to rush the shots.
Hope that’s helpful and enjoy your Christmas!
