Thanks @julien-f
We had a discussion with our developer on Friday and he was recommending we look at ovirt to achieve our goal here, but I am not yet convinced we need to start down that path.
We've run XEN/XCP in our environment since version 5, hence I am keen to continue with it as our core, however customer service is a growing issue for us as our customers are complaining about lack of self-service capability which is fair enough.
Thanks for your help.
D.