Hi,
Happy to hear that 
Better cross encoders that are trained on larger datasets are on my agenda. However, training is not so straightforward. For bi-encoders, you use the other examples in a batch as negative.
For cross-encoders, you have to create the negative pairs. Here, the creation of the negative pairs plays an extremely important role.
I hope I will soon be able to train these models. But setting up the training etc takes some effort.
Best
Nils