Poor Middle Game Execution

I am posting two games, a win and a loss.  I believe the two of them demonstrate my inability to find good ideas in middle-end game positions.  Feed back is most appreciated.

Game 1

Game 2

I am no expert and you are higher rates than me but I feel obliged to give you my input..

In the first game you:

1. Exchanged your knight on d4 instead of leaving it on f3.

2. Your queen and rook were occupied on the queenside.

3. After your bishop sacrifice on f7 you were down on material throughout the game. It did disrupt kingside castling but perhaps it could have been more useful in the endgame.

In contrast in the second game:

1. Your kingside attack and capture of a rook.

2. Your exchange of material.

Led to a more decisive game and you winning. Hope that helps...

Did only watch your first game. It was pretty clear that your bishop sacrifice was a misstake. It was a very good lightsquared bishop with an open diagonal. I really can't see why you wanted to sacrifice the best of your pieces. 

Hey Sam! I have something! Yeah the sac is questionable but... 17.Qa7+ wins a rook! Edit: also 16. qa7+

Also for the first game I would've preferred 11.Qd3 and covering the weak d5 square, and backward d pawn and add further pressure with the rook by castling queenside

10.Qd5 also looks interesting threaten mate, the rook and eyeing the b7 pawn

After move 15 you are down a pawn but he has a backward pawn and you have two connected passed pawns. If not 16.Qa7+ then b4(activating the passers) and Rf-d1(eyeing the backward pawn) would be great plans too

Certainly that bishop sacrifice was a mistake. The bishop was comfortable placed on an open diagonal. And you shouldn't sacrifice pieces to achieve better position unless it is a bullet game -- since initiative is the most important thing in a bullet match. Even though you sacrificed a piece, your opponent would have castled easily via artificial means. 

bishop sacrifice was a mistake