The exposure index is equally sensitive to each of these variables. However, some of these are variables are directly controlled by inputs (habitats, geomorphology), while others are derived through intermediate calculations using the inputs (wind & wave exposure). So you might find that the variables you have direct control over cause the most noticeable changes in the exposure index.
This model does not model storms or their impacts. It estimates an index-based metric of vulnerability to coastal hazards, given the conditions reflected in the input data. Wind & Wave conditions are represented in the input data, but they do not exactly represent storm conditions. See a bit more info here: Coastal Vulnerability Model — InVEST® documentation
Most commonly, this model is used to quantify how the change in habitat distributions will result in a change in the vulnerability of different places along the coastline. I’m not sure if that is the change you are interested in.