Even if GoTN was effected by extend life or Life cocoon, it would still be outclassed by arcane torrent. That said, let's do some extremely basic math (geodew please don't hate me i'm a big noob).
20% of my hp in a raid setting is ~103k, which means every 3 minutes I can do 103k healing over 5 seconds. This does not scale with any secondary stat.
Lets assume a 6 target uplift, and we have two extend life targets. 1 chi = ~500% spell power + 250%x2 on your extend life targets equaling 1000% total spell power every 90 seconds, and 2000% spell power every 3 minutes. However you can't assume extend life is only 50% of your uplift, because of fake uplift healing, it's also going to be a lot higher than this in reality because it scales with our secondary stats. This is also ignoring that 1 chi is 1/4 of mana tea.
So as you can see this extremely basic napkin math shows that GoTN is completely outclassed numbers wise. In reality the numbers gap between arcane torrent and gift will widen because of fake uplift healing and secondaries.
Now lets talk about Gift of the naruu being better for versatility. I really can't see how this is the case. Looking at your logs of Gift usage;
https://www.warcraftlogs.com/reports...ability=121093
A 12k heal a 20k heal on 1 target every second doesn't seem nearly as good as good as off global cooldown chi gen. Even when I used to argue with people about power strikes being better than chi brew, one thing I really couldn't argue was the power of off global chi gen. That was the element of chi brew somewhat redeems it's lower total hps. So by this logic, the power of off-global chi gen applies to arcane torrent. The power to continuously chain uplift -> rems with arcane torrent is what makes it so much better, because extend life is broken. If your arcane torrent allows you to cast another uplift after you snipe with extend life, this will be far more useful/powerful than gift of the naruu.
Arcane torrent being the best racial will continue in the future because mistweaver really needs the mana more than anything. Crit is also the best/second stat for mana tea and rising thunder respectively.
TL;DR chi is overpowered, so that means arcane torrent is overpowered.