I want to keep my rig offline....I recall since w8 and up, it uses a call process to remote servers to validate every day? So I'd have to stay connected if opting for w10?

 

It doesn't matter if it's offline. If it's authorized then it's authorized.

But unless you have a specific reason for 10, then why bother? And I can't think of any reasons why a DAW system would benefit from 10 over 7.

 

I'm staying on win7. "If it aint broken, dont try to fix it"

Decide for yourself what you will Gain using win10 over win7.
And how much time will you spend on installing all the software you currently use.
Form your conclusion based on those 2 factors

 

You can do like normal people do: Install WINDOWS 10 on another partition and experiment with it. I have 2-3 Windows versions on my hard drives all the time. Get a cheap ass SSD $30-50 one and play with it

If it works, make the change, if you don't like, simply boot to 7

 

Windows 10 uses less resources than Windows 7. You'll have more HD space and more available RAM.
I work with Cubase 8, Waves plugins, EW CC and some Kontakt instruments and it's perfectly stable.
I personally don't see any reasons to not upgrade. If you can, better do a fresh install.