Thanks for raising your concern.
Instances that are spawned via autoscaling groups will differ as you told . For this particular reason, in order to differentiate them , we have provided the internal DNS name , provided by AWS for your convenience. If you do not require that feature , you shall disable it in the Amazon Account using Advanced Configuration.
With respect to your request for using display name from agent configuration , it is currently under development and we will keep you updated on the same ( via support ticket you raised too).
Hope this helps.
Ananthkumar K S