I’m glad to be able to help out. The problem you are seeing with your router seems to be very much dependent on your environment and how you are using the device, as for many people 3.211 firmware works great. I am using a AR750s (Slate), which is similar to the Creta you have, while I am on extended travel. At the last place I was staying in December the router was very stable, but in the location I’m now at, my router was unusable until I upgraded to 3.212 beta 1 last week. I was seeing many of the issues you reported and that were reported here:
Since @alzhao, who is the ultimate authority at GL iNet, says to load the 3.212 firmware on your router, I strongly recommend giving it a try. I see that @wcs2228 has already given you the link to it. If you have any problems with the 3.212 firmware please use the forum to report these issues so they can be fixed before 3.212 is released. Also please remember to update to the production 3.212 firmware once it is released. Good luck!