Looks cool!  
This is a really powerful feature. You can use it to control the adapter strengths down to per-transformer level. And you can even use it for multiple adapters.
```python
adapter_weight_scales_toy = 0.5
adapter_weight_scales_pixel = {
"unet": {
"down": 0.9,  # all transformers in the down-part will use scale 0.9
# "mid"  # because, in this example, "mid" is not given, all transformers in the mid part will use the default scale 1.0
"up": {