Defoliation decisions shouldn't be based on whether or not they're autoflowers ... if you've got leaves touching each other or if you have leaves that are covering bud sites, it's always good to defoliate to fix those problems - particularly at the stage your plants are at right now. But don't do a lot all at once.... take SOME leaves off and let the plant recover... if they don't show any sign of stress, you can do more (if needed) the next day.... if they DO show signs of stress, leave her alone until she's fully recovered and then do a bit more, again if needed. The plants are going to start stretching a lot which will help out - but some plants are just too bushy for their own good!
Good luck!