Honestly I don't think transformers are worth it for any kind of TS or tabular data (and there's research showing that). But if you really want to try, I had a good success with this library. It makes it essentially a few-liner to run tons of transformer and other architectures on any kind of tabular data. You may also want to check out HuggingFace model repo for quick solutions.

Probably not. The idea of ResNets is to remove the vanishing gradients that normally occur in very deep networks. In my experience it can often do worse than better, but you can try DenseNets instead.