With the new API to for ´createComponent` to add inputs it could be a good idea to add the options to add Inputs to the modal.

Something like that:

this.modalService.open(MyComponent, { inputs: 
{
    'myInput1': value1,
    'myInput2': value2,
}
});

This does obviously only work with components. I still think that would be a gread addition for the API.
Maybe it could be even typed in a way that the input option is only available if the first paramter is a component.