Hi everyone - thank you so much for your messages, each of them really helps to just clarify things even further. Given everyone's experience and just how individual a lot of the experience seems to be, I think our best option is to just strive to find a good balance and basically just "play it by ear". As some have said, probably not worth getting super hung up on "ultra good", but rather just really work through the side effects and try to fit in with what's doable while still trying to maintain a healthy standard.
I've also spent today throwing together a chemo treatment journal (thanks to @GinGin for the inspiration there) which I'm going to use with Rebecca to make note of any symptoms, mental state, diet / fluids etc - hopefully that'll also give us a bit more insight as to any patterns that pop up and when things might be better or worse, especially around diet and fatigue. Would welcome any feedback on this too :)
I'm so grateful for everyone's help on here - it really is making this process much less scary and more manageable - thank you all <3
George