groomster, first off, congratulations!
Second, when you say a tube is getting excessively warm, can we assume you mean the larger one? And, by excessively warm, do you mean that touching it will instantly raise a blister, or merely that leaving your finger on it is uncomfortable?
BTW, don't worry overly much about touching the tubes; the envelope is simply glass, it's not like a halogen capsule or a 1k tungsten lamp, a little oil won't harm it. Just wipe it off with a soft cloth once in a while. Note: if the markings on the tube are important to you, go easy; some of those will wipe right off!
Finally, it sounds to me as if you are listening to the amp while it is breaking in, something I usually do with a new amp. As a very general rule, after about 50 operating hours, the components get pretty well settled in, and you won't hear much more change until you swap in different tubes. There are certain exceptions that take much longer, but you get the idea.
If it were me, I would live with it for some time before the upgrade. Play a lot of music you are very familiar with. For sure, get it past the 50 hours mentioned above.
Since you have the upgrade in hand, I would certainly recommend that you give it a try, though! And, give it the same break-in period before listening critically. Just keep your options open as you go along, in case you want to change it back.
