From time to time our ISV renews their license package, and with V10 we also need to deploy our regular update packages in Production during the same outage period (overnight on weekends). The fact that we can not merge ISV license packages is a problem because we have to wait 5 hours in LCS to schedule a second package after the first one is deployed.
An alternative idea would be to be able to schedule two packages for deployment into production (one of them would be the ISV license package).