Always nice of you, listening to your customers.
mpkossen nailed it (except don’t really double the prices and that I for myself will never buy a month to month “something”- just too much to worry and forget about, and the ugly feeling you are leaking money even if in fact might be cheaper).
We have to be able to split the number of domains as we see fit between servers for tehnical reasons: migrations, somekind of balancing - between ones machines or between multiple providers in the cloud, reinstalling the OS/upgrading the OS/going for another distro, resource issues, and so on.
I am interested spliting between my physical servers and I don’t think you should worry about differences between physical or virtual, or the number of CPUs and stuff. Simple schema, just count the domains, nothing else, start with current prices, see how it goes for you as it is clear your clients will be happy:
10 domains - xx$/year
50 domains - xx$/year
100 domains - xx$/year
so on.
Because I will do that neverthless, anyway, forced but what we mentioned here - I think you have on a regular basis requests for splitting/merging licenses. At least I will issue one soon
So this is a waste of your time.
Also the support requests I don’t think it will grow THAT much: people usually use and trust a small set of technologies and configurations, and it is best practice and common sense to reproduce one if it works fine for you.
Thanks for considering this.