Sometime you need blood
The actions in the clip were too short and quick and didn't seem to flow. For example, you were moving character hands violently, however body movements were minimal at best. Another example, the time it took to block a shot was very quick, but to react was awefully slow and made the flim seem choppy, boring and linear.
One guy comes in, you kill him, another guys comes, you kill him, the next guy comes in, shoots hero, you him.
Never did one guy comes in, while shooting hero, 3 more people show up, they start shooting hero, while hero kill them in a flowing matter a bomb goes off on the roof and big thingabob comes in.
Also the scenes didn't show any added bonus for removing the blood. Blood is good in "good" amounts. It shows reality in a way
Also two things that bugged me alot. One, never ever can you reload a weapon with one hand (you can see this in the start of the flim which I am assuming the baddie is reloading his weapon)
And two, people with semi autos and pure auto guns don't just shoot a single shot at someone. They tend to shoot alot more than just one bullet. Sometime they even unload on a dude.