Improving the effectiveness of our emails.

Greetings. I'm in the trucking/transportation industry and my corporation sells our trucks as they come off-lease to dealers throughout the nation. We have a distribution list of about 2,000 names. We do not physically sell anything through our website as pricing is negotiated on a deal-by-deal basis. We sent out emails on daily/weekly basis to those on our list in regards to the inventory we have available at any given time. I am looking for ways to better track how effective our efforts are and make our emails more effective in reaching the customers. We currently use Pardot for our email efforts and they can provide a good amount of information in the reports you can generate.

As of the past month these are the numbers for our efforts.
Emails Sent: 50
Avg Delivery Rate: 99.87%
Avg # Delivered: 1978
Avg # of Opens: 687
Avg # Unique Opens: 469
Avg Open Rate: 23.52%
Avg. Total Clicks: 43.2
Avg Unique Clicks: 32.4
Avg Click-to-open Rate: 6.83%

Any feedback/input is greatly appreciated. Thanks for taking the time to read this