Looks like you have a lot of loose hair going on all over your head. How are you locking? Backcomb or natural (neglect), or another method?

From your pictures, your head looks like it needs a bit of maintenance. Might I suggest starting by sewing all your loose hairs into your dreads? (A great way to do this is to gather all the loose hairs to the dread they 'belong' in and rubber band them temporarily so you know where they go. Then one dread at a time remove the bands and sew those hairs into the dread. Pre-sectioning the hair helps you know where the hair should go so you're not grasping blindly about your head. Have a friend help you if you can.)
After you do that, I'd suggest a nice long bout of palm rolling, followed by some serious root rubbing for the hair on the top of your head near the scalp. That should definitely help a lot with tightening up both your roots and your locks.

You're still in the baby stages though. Good dreads take a lot of time, and won't even be considered towards mature until over a year. They're going to be unruly for a while, so you have to give them lost of love and care. The maintenance will plane off to minimal work eventually, but if you want really tight, good looking dreads during the younger stages you have to work on them a lot!

Dreads tend to lock up from the middle out. If you're concerned about wispy tips and want to lock them up faster, felting or crocheting is a great way to speed up the process. You can also gently backcomb them to aid the locking process. (I felted mine to blunt them at around 5 months, and it worked fine. It was just slow going.) You can also palm roll your tips.

As far as wax goes, you don't need it at all. All wax does is make your dreads sticky, and because the dreads become sticky with wax it impairs friction and knotting, making your hair dread even slower. If you're set on using it, I'd suggest getting it from one of the dread companies (Knotty Boy or Dread HQ) and using less than half of the recommended amount, but I'd urge you not to use it at all. Aloe Very gel works just as well, it's natural and it doesn't build up in your dreads.

Dreadlocks arent a fashion statement, they take time and they will look like "shit" for a long time before they look amazing. Unless you pump them full of products (in which case they will look better, but not lock well). When it comes to dreads, dont chase after a "quick fix", you will regret it in the long run. Just have patience. Hell, at three months... you look a million times better than i did.