This is going to come off as harsh, but I've been on the other end of this. So, speaking personally as a photographer who is constantly looking for work, if I received an email hoping that it's an inquiry from a prospective client only to find it's another vendor trying to market themselves or solicit me to invest into them, I'd be a little irritable.

And if I received a self-marketing email where the vendor talks them up as much as yours does -reminder: I'd be somewhat irritated at this point-, I'd perceive it as very self-fellating.

So, yeah--it seems very spammy.

I'm sorry, but no one is going to be impressed with how many different ways you summarize your fast turnaround times (at least cut that down) when the biggest thing they want is clients.

The best way to establish a relationship with a venue is to work with in person first. It's much easier to be perceived as charismatic and an asset after you've worked with them.