Gonna be honest, don’t see how Half-elves are such a problem, or how it’s not at all plausible or equal to the idea of high elves as much as you people seem to think. 
Edit :
Technically I wouldn’t be opposed to the idea of Night elf Paladins, as long as it’s clear the type of paladin a night elf is, is one under Elune’s guidance and not the light Humans use. It’s part of the reason why I want class/race spell colors to be implemented. That way it can be differentiated and understood that a night elf paladin isn’t one of the light but one under their deity. Like a priestess but in plate armor 