I see a problem at the minimum value, becouse it is not known to the public.
of course the 10 is minimum, but if you set 10 and your system have reached an internal minimum of 20,
than the campaign´ll stay on bidding for unknown time.
It also woluld be very informativ to know the min-max of active campaigns.
And a second problem I see,
you don´t validate manialinks which don´t have links or something,
but you still let campaigns running, if these are not accessible!
I think a script to check it, and maybe on third day of no availibility stop the campaign!
It don´t need to stop it by the first one, becouse sometimes the internet fails by it self