How to set up TOR via torrc (difficult optimization)?

Question

Tor

The task is this:

1. Through the torrc file, specify only allowed countries.
   
2. Disable connection to slow nodes via torrc
   

those. you need to select a range of countries and make sure that the connection goes through the fastest and most live nodes.
Naturally, before writing a question, I rummaged through the net and found a bunch of old non-working recipes about countries.
Therefore, so that you do not shove me "obvious" and not working, I write what is already clear and what is not.
Setting input and output ranges

ExitNodes {at}, {al}, {ad}, {be}, {bg}
EntryNodes {at}, {al}, {ad}, {be}, {bg}

And where is the middle range, which is between them ???
#StrictNodes 1
What is it and why is it needed?
Not working deprecated options:

#StrictExitNodes 1
#StrictEntryNodes 1
#RendNodes {at}, {al}, {ad}, {be}, {bg}

Thus, the impulse of the manual, there are even more questions.
Who is not too lazy to understand, write thoughts.