Hi Zoso,
You have excellent growth and should have no problem sporting a fantastic beard at whatever length you would like.
As to your questions,
1) Neckline - I agree with Gato; you have it well positioned and can always drop it if you decide to grow your beard longer.
2) Moustache - I would recommend growing your moustache out and seeing how it does with more length. Eventually, you can make a decision on if you wish to grow it out and train it to the sides or simply trim it along your lip edge (or lower).
3) I don't have a problem with split ends, but I would think that as your beard gains more length you will be able to trim these off. As to beardruff, I do deal with this. I have found that Head and Shoulders shampoo works well for me; I have used both the shampoo & conditioner and the 2 in 1 variety with success. I wash my beard and hair with Head and Shoulders every 2-3 days. I don't shampoo daily as it strips my beard of the natural oils. I don't oil my beard either as I have an oily complexion anyways. You may need to experiment to find a washing/grooming routine that works best for you.
Welcome and good luck.
- Fred

You either live life -- bruises, skinned knees and all -- or you turn your back on it and begin dying - Christopher Pike paraphrasing Dr. Philip Boyce (Star Trek - "The Cage")

Bearded in BC's Thread