So I had my first ever flight in it today...and I got to say that you, GKS, made the best job so far! Well done! I'm actually surprised you made it this good!
However, if you want to make it as real as possible...it still needs a lot of improvement.
I'm comparing this addon to the MiG-21 module in DCS, by the way
A couple of things I noticed is the smart use and placement of the debug controls, you made a nice move there. But the fact that you typed "Yoke" instead of "Stick" isn't really pleasant. A yoke is found on some airliners, it's a control input device that has 2 handles and it's meant to be used with 2 hands. While the stick only has space to use with one hand. It isn't the same. I might be picky, but consider fixing that soon.
The fact that you used a different variant of the Bis cockpit (SAU N, probably the Hungarian) doesn't really bother me though, maybe you really had to design after that variant because of financial reasons or something else.
Now onto the flight model.
I gotta say, it's ok...but what really pisses me off is that it feels like an aircraft that will never stall, which the MiG isn't! The MiG-21 is meant to be very maneuverable at high speeds and also reach them, but falls like a brick whenever you reach a speed lower than 250 km/h.
The Fishbed can also reach 20 units of AoA fairly easy, but the flight model of the GKS will never reach 20 units of AoA even if you pull hard enough; which leads us to the controls!
The ailerons seem to be sort of responsive, maybe it was just because I didn't have the "Aileron Booster" on which I confidently thought it would be turned on as it is an important switch in the cockpit. But the pitch? The pitch is literally non-existent. You have to yoink the stick in order to pull a bit up. I got to mention the MiG-21 is always really sensitive in all axis.
When it comes to speeds...it speeds up nicely, but what bothers me is that the speed exceeds above the maximum speed of the MiG-21. It just keeps going. Keep in mind I was flying at around 100m above the ground, not at high altitudes, still need to test-fly up there.
Also I forgot to mention...since when can the MiG taxi without brakes?
And the sounds...I can already tell you've copied the F-16 sound pack and pasted it into this addon, which I hope will be fixed soon and replaced with a proper sound pack of the glorious Tumansky engine. Buuut, the sound of the switches are really nice, well done on that one.
Overall...despite having a fair amount of downsides and it's able to piss off a MiG geek like me, I'm really happy this addon exists.
The inside and out looks really beautiful, obviously with some things out of place like...the "Beta version" watermark all over the aircraft.
But also the flight model really impressed me when it comes to Prepar3D, every MiG I find for Prepar3D is a total shitshow.
I'm very glad I'm a part of this beta team too, and I hope to see improvements in the future!