Hi mate I've got the same gun.
First off if your playing in the dark, obviously a light will make a difference, if your playing indoors it may help but it's probably more for show and outside you'll never "need" one.
As for the mags, let me save you time and money. BUY G&G MAGS. I've bought box sets of every budget mag out there from asg/ares to the really cheap airsoft systems ones, and in a word, they're all shit.
The AS barely fed at all and would be an absolute joke at a skirmish. ASGs were better but still had feeding issues every ten rounds or so. dboys were ok but I couldn't find box sets and were more or less the Same price as g&g. just get g&g mags from land warrior, I believe they're the cheapest. At £38 for 5 midcap Pmags or £50 for metal ones.