I am not sure there is much you can do. If this is an extension per customer, then do not use wildcards at all and include all of the specific hosts (across all of the test/production environments).
If this is an extension per multiple customers and the host changes per customer, use the wildcard and bear with the review times (I heard they can be surprising sometimes, for the better).
Another option is to tell your customers to have their administrator force-install the extension. You can then provide them with a CRX file that you generated, without any review. You will have to update them manually and they will have to put the updated CRX in the relevant path (though this can obviously be automated).
One tip regarding host permissions - as far as I know, anything after the host is ignored
(this is why they are called host permissions), so no need to include -
Just -
(Obviously, try to avoid the HTTP version at all)
Content scripts use URL match patterns, not host match patterns and there the trailing /* and similar are required.
Also, if you declared content scripts for a certain host (its URLs), you do not need to include those hosts in the permissions key, they are intrinsically included.