I'd like to suggest two macros: \consonant, and \vowel; these would override the built-in auto-detection of a/an to allow the correct "an LED", and would imply \improper (since a proper noun does not have an a/an distinction in the first place).
name \an [object]
LED LED
\improper LED a LED
\vowel LED an LED
UAV UAV
\improper UAV an UAV
\consonant UAV a UAV
uniform an uniform
\consonant uniform a uniform
hour a hour
\vowel hour an hour
'A' used before words starting in vowels: a unicorn, a uniform, a one-armed bandit
'A' used before initialisms starting in vowels: those starting in U
'An' used before words starting in consonants: an hour, an heir
'An' used before initialisms starting in consonants: those starting in F, H, L, M, N, R, S, or X.