Lookie Lookie! Are they SUPPOSED to be that curly? lol. Its only been like 3 weeks now and a couple are REALLY natting up, while others are curly with knots commin along.
Unponytail those puppies and put on a wool hat whenever it is possible for you to wear a hat. I think that would help you along A LOT. They look good so far.
The only problem I'd have with synthetics (fleece, acrylic, etc.) especially at this stage is that some specks and "pills" from the hat are bound to work their way into your locking hair. I don't want to have inorganic fluffballs in my hair, personally. For this reason, I generally stick to cotton and hemp for headwear (I don't do wool, but that's a personal thing - I have heard that the hair-on-hair friction action can help in dreading, though.) You're locks will be cute, I'm sure!
That, IMO, would probably depend on what kind of place it is and what you do. I mean, if you work at a fryer or something all day and it gets really greasy, then yeah, I'd wash more often. You don't want oils or anything yucky to build up - that way the core of your locks will be nice and clean.