How do I play against this kind of position with double c pawn? Continuing my question on double c-pawn.I am studying on this topic and I came to this position.

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

1.e4 e5 2.Nf3 Nc6 3.Nc3 Nf6 4.Bb5 Bb4 5.O-O O-O 6.d3 d6 7.Bg5 Bxc3 8.bxc3 Qe7 9.Re1 Nd8 10.d4 Ne6 11.Bc1 c5 12.Bf1 Rd8 13.d5 Nf8 14.c4 


In my opinion, black's position is better here due to the double knights. However, I couldn't find any concrete continuation in this position for black. 


Ng6-Nh4-Nf4 seems intuitive but then, I don't want to give up knights easily.
It's hard to exploit the double c-pawns.
Bg4 swapping the knight for bishop seems appealing but I don't know if this is good as this gives white double bishop advantage in endgame.


My question is that  


Is my analysis true?
Is 11. ...c5,the pawn break good (or are there any mistakes in the previous move)?
Are there any other ways to break this position?
Who stands better here?
ad 1: Partially, yes. Ng6 is a good move but it will get surely met by white's g3. That's natural. Still u want to move your knight from f8, this square is for your rook.

ad 2: Of course c5 was a good move. You played the opening correctly!

ad 3: Yes, the natural plan is to prepare f5 break. Something like Ng6, Rf8, Nh7, f5

ad 4: I would say rather equals. White has pair of bishops but c-pawns might be an issue later on. Good position to evaluate players' strength. Good luck!