If it is just to see an indication to how popular your work is, then it shouldn't matter if everyone clicks install or not. It will be the same with other modifcations, so yours will still be more popular then another (or not

).
The whole "Install" is ment as a service to users of a modification. It adds the modification to their UserCP so they can easily find it, and they subscribe to an
opt-in mailing list for updates. No way we will be forcing clicks and thus forcing users to opt-in. If a user don't want to be kept up2date, then this is his/her choice.