That's a really good point. It seems like most English consonants have roughly one way to pronounce them, particular as a first letter in a word as in an acronym. I guess I should've looked for acronyms built on Ch, Ph, Sh, Th, Wh, Ph, hard or soft C's, and of course hard or soft G's (ginger, gypsy).
Here's a soft G word making a hard G acronym, and a hard G word making a soft G acronyn:
GAD - Generalized Anxiety Disorder
GEMA - Gas and Electric Markets Authority
Some other non-G examples:
PAL - Phase Alternating Line
PAWS - Phased Array Warning System
SWF - ShockWave Flash
They're much harder to find though.