When you speak Serbian you understand 3 more languages !!

I work in culture, Serbian living in Prague, I speak English, Slovak and some Czech ("its Slovak part" :-)) love communicating with people.
Serbian is as easy to learn as any other language if you are motivated :-) i have no strict "methodology" and would look for the ways that most suit you while learning a new language.
with knowing Serbian you will have 0 problem communicating in Croatia, Bosnia, Montenegro ... If that is not a bonus, i do not know what the bonus could be :-)
and , even with travel restrictions you will have enough opportunities to speak Serbian in Prague ...