Low open rates

Hi. I have a lot of other questions, but going off of what you’ve said here...here are some things I’d check:

1. Are those 200+ subscribers valid emails? I’m not sure if you have double opt-in enabled or not. If not, some could be burner emails, subscribed just for a discount. Do some validation and get rid of or correct any email account that’s wrong or bad.
2. Check our subject lines to make sure they include personalization and are aligned with best practices. I use two subject line testing tools in case you need them: 
   subjectline.com and omnisend.com/subject-line-tester/
3. Do you have a segment of 30, 60, and 90-day engaged subscribers? VIPs? Send only to those who have been most engaged with your campaigns recently. Then slowly open up from there. During major holidays, open up to more if not all valid subscribers.
4. What’s the deliverability rate? Check if you have issues getting into their inboxes. (ie: your SPF, DKIM, and DMARC record setup)
5. What’s your spam rate? Unsubscribe rate? If those are below your industry standard, you could have issues with content quality or perhaps your cadence. (not sure how often you campaign per month). 
6. Lastly, is your content valuable and engaging for the segment you’re emailing? I assume you’re sending this segment content that they care about.

That’s all I can think of now...more may come later :)