Well, the obvious way to answer this question is to analyse their download statistics. If more than 1% of users download the CD images, they may still want them around. If not, then leave it as just DVD.
To make things simple, they *SHOULD* have a full-release installer DVD. Lacking that (if they do lack it) would be a deal breaker for me. I would NOT bother with downloading 5-10 CD images, and I would NOT install a livecd (since there is too much FIXING to do to a livecd before it becomes useful).
For anyone worried about booting/installing from usb sticks... you can use the DVD install image to build a bootable USB. I do that from time to time with the Fedora install DVD image. I just put it on a 4G usb stick.... they go for what... $3 or there abouts?
In summary.... the ABSOLUTELY ESSENTIAL image to have, is the install DVD image. Everything else is bonus and DOESN'T COST ANYTHING, so it certainly doesn't hurt. If you want to decide whether to bother with the CD images or not, just count how many CD downloads actually happen. If the number is ZERO, then there's no point in it.