No need for a right back imo. If we sign a backup, once Richards finds his fitness we'll be back to the situation we had last year with three players fighting one position. Milner and Boyata can do a job there if needs be.
Dont get the obsession with wanting a new CB, personally I think any defender would look poor in our system given the amount of space between defence and midfield. This will improve as players get used to Pelles tactics, they just need time. Kompany, Demi, Nastasic and Lescott is more than enough cover.
Cant see anything happening in Jan, had a feeling Dzeko might leave after the Plzen game but I thought he looked much better against Munich and could still well be an important squad player till the end of the season. It wouldnt surprise if he did leave in Jan though if a good offer did come in.
Only position we desperately need to strengthen imo is central midfield. A proper world class CM would complete our squad but I suspect the likes of Vidal, Gundogan etc won't be available until the summer.
Although its a bit risky I would like to see more faith in youth rather than spend more money on signings. Something Chelsea have failed to do after investing millions in their youth development. Rekik and Denayer will hopefully be important squad players next season once Lescott leaves in the summer. Lopes could also do a job on the left.