Open Stack

We're running a system with a really wide variety of node types. This
variety (nodes with 24GB, 48GB, GPU nodes, and 1TB mem nodes) causes
some real trouble with quotas. Basically, for any tenant that is going
to use the large memory nodes (even in smaller slices), we need to set
quotas that are high enough that they are useless when it comes to all
other instance types. Also, instances aren't comparable across our
range of hardware either.

Is there a clever solution to this problem that I'm missing? Is anyone
else running into this sort of properly operationally? I'm a little
bit worried that a slightly too simple notion of quotas has been baked
into openstack at a fairly deep level.
thanks for any insight..
 -nld