Just to get into some CPU specifications of single thread performance as taken from https://www.cpubenchmark.net/ which is key to the performance operation of the RoonOS in a ROCK deployment.
So the lowest spec NUC, the NUC5i3 I had running from 2017 to recently with a 90K library, had a single thread performance of 1,241
A RevB Nucleus (which I understand uses a NUC7i3 board) has a single thread performance of 1,391.
A RevB Nucleus Plus uses a NUC7i7DN board, with the quad-core Gen8 CPU with a single thread performance of 2,156. However, if you don’t need the multi-endpoint support then a NUC7i7BN gives 2,261 but Intel is working that CPU harder at 28W TPW to get that power out.
A NUC10i3 gives 2,265 circa the same as the Nucleus Plus for single thread but just a dual core for the same overall power as NUC7i7BN
A NUC10i5 gives 2,231 also in the same ballpark, but the same overall power as a Nucleus Plus with quad cores
A NUC10i7 gives 2,457 which is not much more than the i3 or i5 on the important single-thread performance but the 6-cores give it overall performance potential if the OS can leverage 6 cores/12 threads in parallel, or the workload requires it.
As a comparison, a NUC8i7 gives 2,575 but at the 28W TPW.