I agree about how hard it is to level a weapon and unlock the goodies. I main LMGs and have given up on unlocking anything of worth. I'd love to be able to unlock the laters tiered guns and attachments, but doing so would require putting my life on hold. I game when I can, casually, when time permits, not the other way around.
There must be many people like me who are just as frustrated with the amount of hours required in grinding even low tier unlocks.
The next biggest issue I have with this grind is that I have completely given up on trying any other classes or weapons. I'm forced into grinding my main LMG due to the difficulty, I have no time remaining to try other weapons or classes.
Its a shame that DICE has made it so difficult to try the other weapons and classes.