I've recently tried extended for a bit, just in case your wondering l suck at dts. I've been playing around with mono-Skeelz for a while now.
Heres my deck as of now; Chiara Cr, Sandro, Dr Falkenstein, Belgosi, Minerva, Aylen, Michael, Tomas
If you're planning on keep playing mono Skeelz then you really need to get Sasha and keep Sandro. I would reduce the number of stars in your deck. I would also try to replace one of your 4* or 5* with Dwan, a good 2-way card which i find awesome for DTs.
A goo idea in DT's is to play quickly, try 1 or 2HKO as much as possible, but you also need to be weary of cards that force penalties on you, as too many of those means you will lose bp I you lose a match, here is my deck Ice Cold Killers