I assume you are using the internal dac of the streamer? In that aspect you may notice more of a difference than say comparing the 2 as a transport only. I've had quite the handful of these budget streamers, the CNX2 being one of them but only the original Node. I've used external dacs with all my streamers and of course with the transports..but I've always tried the internal dacs on the streamers to see how they sound. I'm going off memory but I recall, subjectively, that the CXN2 had a warmer signature and more focused slightly narrowed soundstage. First Node I'm comparing it to.
Is it really worth moving from the newer Node to the Cambridge? Tough call. I doubt it will be some eye opening difference, probably more like subtle differences. You could spend the money upgrading your current power supply if you are happy with the current software. In my opinion if you want a big true upgrade you need to step up to the likes of Innous or Aurender, maybe Lumin. There are a couple others but you get the idea.
To me the Ifi Zen Stream and Primare Prisma I or II transports are good sound quality for the money. Never tried the cheaper Eversolo or Pro-ject that I consider to be part of the budget streamer lines. I can understand why others would think moving to the Cambridge would just be a lateral move. But depending on your budget and your plans to upgrade the rest of your system in the future maybe you are just looking for something a little different or better. If you don't have plans to keep spending and upgrading your system the Cambridge might be all the subtle differences you ever need. From a budget standpoint if you can sell the Node for a decent amount, pick up a used CXN2 (which I see a few of them now) for a good price then make the move. The CXN2 is a nice machine, looks good too.
I guess it just comes down to what you want to accomplish. I've only been into streaming a couple years, and if I could go back to start I would have probably waited for a pricier unit from a maker with a track record of making high quality streamers. You are going to end up there eventually if you are always chasing better sound.
If you will be content with a modest system the Cambridge is a nice unit, but so is your Node. And like others have said, upgrading the internal power supply and then adding a linear power supply to your Node (when cash permits) seems to be a great upgrade. Depending on the rest of your system that may be all the upgrade you ever need. You could also upgrade the power supply if money is burning a hole in your pocket, then the next time you have the itch you could look into a nice external dac. So many choices in hifi lol.
Everything I mentioned here is just my opinion and I wish you luck. If you do make the switch to a different streamer I hope you come back and share how you feel about it. Happy Holidays everyone!!