An unexpectedly non-trivial task: a hassle-free wireless keyboard + mouse kit for 3-4k?

Question

Keyboard

Last year I found that in the price range up to 3000 rubles. there are no decent subjects. I had to worry about the fact that a wonderful wireless kit from Logitech 4 years ago suddenly died (still with the old logo), to replace which I immediately bought the same one, but with a new logo ...
Unfortunately, the keyboard missed pressing. I went and exchanged for a set from another company, paying a little extra. He had a mouse. Began to study the topic, spent a lot of time. I would never have thought that such a problem is even possible and I will read the Internet for days in search of normal peripherals. Went to the store again. And further. After the fifth exchange, I resigned myself and stayed with the keyboard and mouse from different sets. As a result, two USB ports are occupied - not critical, but again I needed a wireless kit, and this time I want to make the right decision...
Advise a suitable kit without missing clicks and hangs. Very desirable from Citylink or DNS - there are no other stores in the city. Budget 3000-4000, plus or minus.
PS: to the moderator - the question is really complicated, please do not change this parameter.

Answer 1

The air is not the same as it was 4 years ago. The people have a lot of wireless speakers and other devices.
Thermometers outside the window and those periodically throw packets on the air.