We've been down this path, and don't think it is a good idea. We have run the hub software on faster hardware, much faster and much more expensive. Guess what: automations run at the same speed. Why is this? A faster CPU does not increase the speeds of Z-Wave and Zigbee networks, or the Lutron main repeater or SmartBridge and ClearConnect radios. So you could pay a lot more for more CPU and not have a very satisfying increase is overall system performance. This is independent of the issue that some users have reported about hub slowdowns, which is not a hardware issue.
So our conclusion was, while they are certainly people like yourself who would pay more for a bigger/faster hub, it just doesn't seem like a good plan unless there were some markedly different overall system performance that resulted from this.
