Congrats on his mission call. I hope all goes well for him while he is gone. One of my friends growing up served a mission in Russia. No major worries to speak of other than almost freezing to death. 
I personally didn’t go on a mission and I know baptisms are important to some but I really enjoy service. I wish I would have had been able to choose to go on a service only mission and I think I likely would have gone. I did explore “service missions” later in life once I returned to church but serving (essentially working) part time for the church in different capacities is far different than living somewhere else and wholly devoting your time and energy to serving the people around you.