Hello,
Since bandwidth usage is the only automated way an acccount gets suspended (by default) that would be the only reason that would be suspended, thus it wouldn't really be needed. If the admin suspends the accuont for another reason (say abuse) then there should be contact with the user anyway. Also, DA suspensions assume that the User cannot login, so as to not be able to change any files/paths that DA changed, so out of design, we wouldn't be able to do it.
However, what may be useful to you would be to have Users setup their own bandwidth limits for their doamins, independant of their User accounts if they still need to be able to login.
User Level -> Domain Setup -> domain.com -> set a lower bandwith limit.
What that would do is have DA supsend the domain for them, but not their DA account. They would still be in control of it though, since it's their own limit, not the Resellers, so 99% of Users would always have it maxed out to the User limit anyway.
John