I have seen that several mods offer Dawnguard compatibility add-ons as separate *.esp files. That seems a far better way to me to handle things - is there a reason why some mods choose to include the Dawnguard dependency in the main file? Who else plans to add a Dawnguard dependency to their mods and require the DLC for future versions?
I have found the topic that gathered a list of mods compatible with Dawnguard, but none with a list of dependent mods. I'm aware I might be somewhat of a minority not owning Dawnguard, but I can't imagine I'm the only one around not buying it at all or at least waiting for it to be on sale.