I'm a product marketing team of 1 - what would you recommend as easy, every-day tools/actions that will help me understand our customers that little bit better?

1. Listen to sales/CS calls. As a team on 1 you can't be on every call but make it a weekly habit to listen to at least 5-10 calls (you can listen at 1.5 or 2x speed 😊). Be strategic about the calls you listen to - use keyword search or tagging for key topics of interest that are relevant to your business like competitors, pricing, implementation, ROI, etc. This will give you great insights into what your customers and prospects care about and how your team is responding. 
2. Read G2 reviews. There's so much information shared in these reviews about what your customers like or don't like and what matters to them. You can also make it a fun activity with your CS team - once a quarter host a happy hour and each one reads a couple of reviews out loud (record it and you have a great video to share on social). 
3. Follow NPS comments. If your team is running NPS surveys, comments left by your customers are also a great source of intel. You can btw, easily turn these comments into customer quotes that once approved can be used in your marketing content, social, sales deck, etc. As a marketing team of 1, you need to multiply yourself so this will allow you to kill 2 birds with one stone. 
4. Set a goal for yourself to talk to at least x customers every quarter. It can be a formal interview or just listening in to a customer QBR.   

Well first of all, it’s always tough to be a team of one. You are definitely going to have to ruthlessly prioritize and as a team of one, it can be easy to get stuck as the sales content/collateral & product launch factory. So with the spare time that you have, I think a few things that can help you understand the customer a bit better perhaps in order of ease:

1. Sign up for daily newsletters from the industry trades that you’d want to cover your launches
2. In those newsletters sign up for the webinars that come thru, or webinars from competitors that you think your target market would be interested in
3. Set up and automate reports from your CRM to your inbox anytime there are deal notes…things like competitors mentioned, closed won or closed lost reasons – obviously this is dependent on good CRM hygiene, but try and get sales folks to put notes in the system and help them see how it will help you better position products for them to sell
4. Get on calls, or listen to recordings if you have the tools…this is usually the most helpful way that I’ve found to get into the mind of a prospect/customer whether it’s to sit on calls with sales or customer success and hear how customers are articulating their needs/pain points
5. Go to industry conferences either as an exhibitor or as an attendee to hear sessions and meet customers in real life!

Good luck!