If Kentico has the existing tables for email analytics then why not use Kentico? Maybe I'm not following what you want. For instance, with SendGrid, I can see some similar things like I can see in Kentico:
- Email opens
- Link clicks
- Unsubscribes
In SendGrid, I can see the following (but not all in Kentico):
- Global Stats
- Category Stats
- Category Comparison
- Subuser Stats
- Subuser Comparison
- Geographical
- Email Clients & Devices
- Mailbox Provider Stats
- Mailbox Provider Comparison
- Browser Stats
- Browser Comparison
Plus these:
But as I mentioned, Kentico doesn't have all of this so you'd have to create custom module classes to store this data (if you're able to get it out of your SMTP provider) and write it in those tables. Not sure why you'd want to do this vs. use the UI that is already available but to each their own.