You see there is a difference.
Afterglow is a cosmetic upgrade with nearly no benefit what to ever, thus, a waste. Your going much to far into what your saying. For instance, my Excalibur does more damage for my RDM, thus, worthy investment. A Mythic NIN does more damage, again, worthy investment.
Aftermath MNK gets glowy hands, not a worthy investment. Afterglow WAR gets a giant glowing Axe, again, not worth it. If afterglow improved stats, I might see it as worth it, and not selfish.
Now if the stats were
99

MG:+52 Delay:+86 Attack+40 Enhances "Counter" effect V "Final Heaven"
99-2

MG:+62 Delay:+86 Attack+50 Enhances "Counter" effect VI "Final Heaven" Afterglow
Might have something there, an increase in DMG, Attack, and Enhancement. However your comparison is bad imo because your talking about
real improvements vs visual improvements.I still see any afterglow as a selfish use of supplies & resources, simple as that.