I've used the liquid. It is fairly moisturizing and it does lather up well for me. The smell is AMAZING too.
My dreads are at just over 6 months and I have not had any dandruff issues.
I'm sure if you get 1 of each to try out, the other will not be wasted. You can use it as a body wash/soap. 
Definitely leave it be. I did TnR and mostly it came out. I left it mostly alone and now, after 6 months, there is still loose hair but there is definite progress.
From what I hear, fine hair dreads just great. In fact, because the shed hair has nowhere to go, it will eventually thicken up.
I have personal experience with dreadlock extensions as well as installing them on people of various hair types. If you do put in dread extensions you will have head and neck pain as well as hair breakage. Fine hair breaks pretty easily also your head and neck (and in some cases, your back) will hurt because it's not used to carrying so much extra weight all of a sudden. I'm not trying to scare you off of extensions however, I wanted to warn you of what to expect. This will be very different from having your own dreads because the extra hair weight will be gradual.
Regardless of what you choose, time to tune out that negative nancy who is poo-pooing you every step of the way. Do what makes you feel good and happy and just don't hang out with them :P
3 weeks is really too young to see much progress actually. I have naturally curly hair and it's honestly a blessing in the end. The first month was mostly loosening up and at the second month I started to see some tightening and loops started to happen. Now that I am at 4 months my curly hair makes my dreads look more like curly hair and less like the mess that some people complain about.
Be assured, the curls will eventually create awesome dreads. I have some that are already rounded-out locks.
An another note, you say you are at 3 weeks and have only washed your hair twice? Try washing your hair at least 2 - 3 times each week because natural oils from the scalp can inhibit locking. Also, if you make a water bottle of sea salt spray you can spray them a couple hours before each washing and that will help lock them up too.
Hey Pip, welcome to the site!
Your dreads look great and hopefully you got some good information on "maintenance" when you came here.
Try to lay off of products that have SLS (Sodium Laurel Sulfate) and Alcohol because those will dry you out.
Massage the scalp with your fingertips in a circular motion and that will stimulate blood flow to the scalp. You aren't going to see results over night but over time your gaps will fill in, your locks will lock up naturally and your tight dreads will probably loosen up a little bit more becoming thicker looking.
Some of those TnR will probably loosen up a LOT or completely over the next month. Try not to re-do any of them though because it will just repeat the process from the beginning.
I used TnR and at 4 months a lot of my tips have blunted and locked up on their own while some are still loose. It will just take time and patience to get the results you are looking for.
Brighter colors tend to fade faster. For instance, greens are the smallest color molecule therefore it slips from the hair cuticle easier and will fade faster than reds. Reds fade pretty fast but are really hard to remove all of the way. Also, in order to get true to tone bright colors, a lot of people with darker hair have to pre-lighten with bleach and bleach will sometimes blow out the hair cuticles making it harder for dyes to stay in place. If this is the case then it's good to get a nice porosity filler on the hair prior to coloring to help fill in the gaps in the hair's cuticle.
I *think* that the standard forums is pretty... standard... lol! Like all the forums. Featured forums are specific topics that are popular or of importance that are "featured" and therefore stand apart from the rest. I'm not sure if there is a method to this or if they become featured by clicking a button by the admin, kind of like a "sticky" thread.
The same can be said of everything else in this regard. Maybe SE will correct me if I am wrong.
Anyway, welcome aboard! :D
Totally normal and I used TnR. Since I have a propensity to sleep with my body facing the edge of my bed, what I had to do to trick my body into sleeping on the other side was to flip vertically (head at the foot of the bed and feet at the head of the bed.) It definitely helped and most of my hair evened out-ish after doing this for the same amount of time prior to switching.
