One thing I should point out that most people (including people way shorter than you) dont know how to hold rifles (especially AKs) properly. The usual inclination is to put the toe of the stock up high in the pocket of the shoulder and this forces you into a goofy chicken wing bladed trap/skeet shooting stance where longer is better.
Like this guy, dont do this
Instead, stand naturally squared to the target with your feet slightly apart as if somebody was trying to push you over, bend slightly at the waist and bring the stock closer to your centerline, shrug your dominant shoulder slightly as if blocking a punch to the jaw and you should look something like this.
You may want a little more length still but try this first. There are recoil pads for the underbarrel grenade launchers that you can get to add a little length as well.
Speaking from personal experience solely, in general when shooting real rifles; having a stock thats "too short" is far better than "too long"...if you can bump your length up without going too far then you get better recoil control etc but if its too long it forces you into goofy stances and makes general weapon handling awkward (especially when wearing more than a tshirt). Recoil control in airsoft isnt exactly a concern so I wouldnt worry about that so much obviously.