I think you have your terminologies a bit mixed up. A NIT is a measure of light from a display device. Nothing to do with a video level.
8 or 10 bit bit peak white can be whatever NIT value gets displayed on the screen, depending on the display technology. It is a function of the display.
OLED's and newer LCD's can already get up to about 1000 NIT's. There have been calls for 5000 or even 10000 NIT displays.
BT.709 (HD Format) or BT.2020 (UHDTV) define the various parameters inside both of the formats. Both only define Standard Dynamic Range (SDR), nothing to do with High Dynamic Range (HDR). BT.601 is for Standard Definition and has not been modified in anyway.
HDR is above and beyond those two standards, which is still being argued in international forums. At the moment HDR can only be seen in UHD implementations.
I could go on, but its sunny outside....
I have the KRIX Atmospherix AS (larger ones) in my ceiling in a 5.1 setup and couldn't be happier with the end result. Yes they are expensive at RRP $445ea (I paid <$400ea) but the are a full enclosed speaker (backbox) with separate woofer and tweeter design that gives a great overall sound in my HT room.
I was actually going with the metaphor of comparing top end TVs and top end jewellery and describing diamonds as crap when you can have sapphire etc.
But I can't fault you for not divining that. I really must not post after several beers. Poetry, what was I thinking?
I'm not going to bother listing the many cons of plasma panels as there is no point... since they're not being made anymore. Best to focus on what is available as brand new now and what may come in the future. To do otherwise is simply staying stuck in the past.