The NKRO is actually important to me. I occasionally play an old-school game called Subspace Continuum. So many boards key lock on me if I'm holding CTRL+SHIFT+3 Arrow Keys+Tapping Spacebar to shoot. I had a terrible old logitech PS/2 keyboard a long time ago that handled it fine. I replaced that with "fancy" new microsoft keyboard, and then I had key locking like crazy. Same problem with a Logitech G510. Drove me crazy. Ended switching to this Steelseries 7g with Cherry Blacks but the keycaps are terrible. Currently 6 keycaps are completely busted, I've moved keys around to replace the ones that I use all the time but still several key slip off if I'm button mashing hard enough. Super frustrating.
I was definitely leaning towards browns already so your input has affirmed that. I will go with browns. Any reason not to get the Hassium Pro? I don't need backlighting but I also don't mind the font on them either. I no longer am considering a Das.
Any good mechanical with diodes in the matrix would see that as 4KRO+mods, in other words, NKRO is useless as others have said, you only need a properly implemented matrix and standard USB 6KRO.
Aside from the font and the price, the Hassium is a decent board. I'd rather get a Ducky for cheaper (Zero, Zero Shine or Shine), but if you like the Déck, go for it.
If you don't need backlighting the CMStorm QuickFire XT is great value, good board for the price.
Also, do you really need full-size? TKL is great for gaming since you can move the mouse in closer to the other hand.