Believe me you aren't alone. I've posted threads about this ever since they removed elemental primaries and called them out on the lame ass excuse Luke said about 'variety'. There have been tons of people talking about it (on here and other sites like reddit), and making suggestions like this for ages. Honestly though, I don't expect primary elemental weapons back until Destiny 2 where hopefully there will be better AI and consistently more complex bosses/scenarios. If it happens before I'll be pleasantly surprised.