Do not take this seriously, I am satisfied, in principle, with any non-rude option. It's just that sometimes YOU come up with such interesting ideas that I can't ignore them. :D
My favourite and most mysterios idea is "G", it's author removed everything that was superfluous in my nickname. x)

*the 3rd point, "Braga/Brajka" is a transliteration of the Russian word "Брага/Бражка" that also means a type of alcoholic beverage. Just accordant words.