Personally, I think it all comes down to how much you want one of the Godox bigger-than speedlight options. That's pretty much all the Godox system can give you that the Nissin Air system can't at the moment.
I LOVE the NAS system so far
I would say keep it, then. If it does what you need and you love it, you should keep it. Most of the reviews I've seen have placed the Nissin UI/UX far above that of the Godox gear, particularly the X1T transmitter. And according to elv on flashhavoc, Godox would never have come up with the Xpro transmitter on their own were it not for Adorama pushing for a better UI.
Every review I've seen say Nissin is inferior to Godox (B&H, Adorama, Amazon, YouTube, FujiRumors ...)
I haven't seen any reviews that give Godox clear superiority over anything but having bigger lights. But I tend to just use what I like and stop worrying about how it reviews once it's in my hands.
I've read Godox being better and more dependable
Godox is much cheaper
Just me, but these two things tend to have an effect on each other in a reviewer's mind. The cheaper something is the less dependable it has to be to be considered good, and the more expensive something is the more dependable people expect it to be. Nissin gear is more expensive.
Godox has way more options for lighting
Again, true. Nissin has no equivalent to the $65 TT600 manual-only speedlight, or AD600, or the plug-in AC-powered studio strobes that are in Godox's X system. But if you don't need them, does it matter? If you do need them, then that might be a more concrete reason to swap than simple system anxiety.
So I'm kinda at a fork in the road ... Should I break down and buy the Godox transceivers and flashes or stick it out for Nissin?
Nobody can make this decision for you but you. But you might want to really solidly weigh what your needs are and why you love the Nissin system. Most of the folks moving to Godox are doing so partly because of the price tags, and are willing to put up with no manufacturer service, a copy lottery, and inadvertent beta testing as an early adopter. Not to mention a lot of firmware updates.
I have two $65 TT600 flashes. I adore them. They work as advertised in HSS over radio with both my Canon 5DMkII and my Panasonic GX-7. I expect they'll work that way with my X100T when I get an XPro-F trigger for it. But. If I put one of them into S1 or S2 optical slave mode and then activate MULTI mode, the thing will repeatedly flash until I turn it off. The later bursts in the MULTI mode re-trigger the optical slaves, despite having the number of bursts and frequency data to know how long the slave should be turned off for.
Nobody integration tested those two features together. And that's the engineering on a $65 manual-only flash.
Am I likely to use it that way? No. But does it bother me? A little. It's a $65 flash, I knew what I was getting, but it does hint at more corner-cutting than I'd like.
I also have a major issue using the TT685-C as an off-camera slave to my GX-7/TT350-O combo (can't use HSS or TTL if I'm in bright ambient conditions). I'm also ticked off my XPro-C doesn't have single-pin mode. Also that it needs a USB C cable to be firmware updated and they didn't put one in the box. And as an OSX user, it's a pain that I have to run Windows to do a firmware update on the gear. Not to mention how many updates I've had to do (although, as a Fuji X user, maybe I should be happy at the kaizen). I'm happy I chose Godox, and I'll continue to buy into the system. But I'm also happy to complain about it.
No system is flawless. You may find if you get your hands on Godox gear, that it's not necessarily going to fulfill your dreams of what it is.
Godox is still cheap Chinese gear in the end.
See also Robert Hall's Youtube video on all the things he hates about the Godox system.
If after all that, you still think you want Godox gear, warts and all, then you may have a point.