Kind of surprising that full back with just 10 to tackling and marking, though that indeed can be enough. In my first season with Torino my leftbacks were like that and they did a decent job. Nowadays I don't accept less than 13 in one and 12 in the other.
Steven Caulker looks like a great capture, I'll be looking forward to how he comes out for you. For me he was a disappointment. He performed poorly in the first matches I used him, enough I left him at home almost always, when injuries forced me he began to perform well, then after two good matches, an injury took him out for two or three months, so I sold him for €6.5M as I didn't feel like betting on him again and I needed the money.