the trailer looks good... bit boring (to me) but it LOOKS good...
how did you make it? what was the budget? it looks like a proper feature film with a budget (explosions, camera, lighting etc...)
But the lack of good music and good sound (explosions, shooting etc...) makes it boring, you can't use long boring music for the entire trailer, you could use some fast music for the second part where there is a lot of action going on... and SFX sounds would help.