It's my personal preference to wait for the perks to be unlocked instead of buying them. This is for 2 reasons, first is to make it worthwhile to level up and second is because it seems illogical to me to spend SP on something that will eventually be unlocked anyway and your SP will be gone.
I totally see your point, but since you get 2 points every level and 1 point in-game every now and then, I know I will have more points soon enough. But I get your point. I just really want the 3 attachment perk because I love the MTAR-X and the silencer and foregrip steady it a lot, but I don't like the blind spots from the iron sights so I want a reflex or something. Not a tracker sight tho. No offense to those who use it, but I find it the same as the target finder on BO2. Don't take the easy way, get some damn glasses if u can't see.