I think most Czechs want to play in Czech.
I dont ...
Most names of places, spells and people sounds horrible in our language ... not many people play with words carefull enough to make it sound interesting. xD
For me the issue with my localisation is that I do not know 5ed in Polish (and my grasp of DnD in general is better in English too), so I raked my brains backtranslating things. Is Czarownik a Sorcerer or a Warlock, for instance?