DNC can hold on their own very well, yes, you can Campaign it. I do not know of any solo spots, but in the coming update there will be more areas available to do Fields of Valor on, with some for you to do with your current lv on. One such place is sky, which is a little higher, so I assume there will ought to be others below to somewhere your lv to do.
Horst needs a 1 minute, 15 foot doom aura. Get in, get out, or @#%^ing die.
...draining with sambas is kind of like you smack the thing and as you smack blood flies out... normally the blood would just you know fall and be red an what-not, but, with the samba your all whacked out and decide to drink the blood as it flys out. thus not adding MORE damage just taking more advantage of your damage. at least thats my take on it.