If the install media footprint keeps growing, eventually it isn't going to fit on your standard DVD anyway. Is Big Blue going to release Windows on BlueRay? I don't think so Tim.
I used a USB Flash drive to install Windows 10 on all our computers,Burning ISO DVD's is a thing of the past for me.
I have a dedicated customized thumb drive for each of my PC's. My product code is entered automatically with a PID.txt file and I add OEM info for that PC that shows up on the system page. Last time I counted I had 24+ thumb drives on the go for various things.
I actually don't care for the free upgrade. I certainly won't do it come July 29. I will not do it at all if it won't be possible to do it with some sort of ISO.
What exactly is a mandatory update? If you're referring to the upgrade to 10, then I won't get it, I did not instal the "upgrade" apps. If you are talking about the usual Windows update, then I have it on manual, so the system does not download anything unless I say so.
Setting regular updates to manual, may be thing of the past as MS declared. If one would go by recent experiences some updates may be dependent on previous ones, so if you miss one you may not get next one even if you wanted.
In the past, I always evaluated each update and installed it if it meets my criteria but in the future it may not be possible. I'm not going to miss opportunity to run W10 just because of that.
Ms provided all the updates to download and install in case it wouldn't pass thru WU and if that continues, you might be able to do it like that if and which you want.
Windows 10 is killing them but other companies will still use them.