There's so much potential in small scale niche products - you don't need to think that big

I have been a Java/JS developer and 'wantrepreneur' for years. My goal is being able to quit my dev job to work on my own business, but none of my 1000 ideas seemed "significant" enough to be able to replace my ever growing dev salary.

It was during my second maternity leave that I decided before I went back to work, I would make a decision on what type of business (digital products, ecommerce, service, saas, etc) and what niche/problem I would focus on.

After consuming way too many podcast episodes, I stumbled upon Indie Hackers episode with Jordan O'Connor of Closet Tools (Poshmark automation) and learned the potential of a small niche product making $20k+ MRR as a solo bootstrap founder.

--------- What I learned from that episode that changed my life ---------

• I can do this as a solo founder and there is potential to make way more than my desired 10k MRR goal
• Niche audiences talk, and there is great potential for word of mouth growth
• Small audiences have problems that are too small and not profitable for larger companies to solve, but for solo founders they are great opportunities with little competition
• if you choose an interesting niche with profit potential, you can build multiple products ranging from small to large over time and serve that market over and over
• Think about the communities you are already apart of, and that you know some of their problems (lurking in niche facebook groups for help posts is just one way)
• You can do this even if you have kids

--------- How this has played out for me so far ---------

• 5 years ago I built a small script for a previous colleague that owned an Etsy shop. It was just a script behind a google form that helped Etsy sellers post their listings to their social profiles. I made a post on reddit but then kinda forgot about it. Only paying attention when people emailed me with questions or issues.
• 2021: I decided to start collecting sellers' email when submitting the form so I could build an audience & send updates, and even charged some sellers a one time fee to have their stuff run daily. (list is at 700 with no marketing other than a reddit post and a single blog post, made $700 to date from one-time sales)
• Q1 2022: Committed to building a SAAS frontend for the existing script tool and other helpful utility tools to help sellers grow their shop; learned a new stack (Firebase, Vue)
• Q2 2022: Getting ready to release first "polished" version of the app and start marketing to my audience to sign up and try the free version or upgrade to Pro
• Slower progress than I would like, but only able to work on this 5 hours per week after work and the kids go to bed

Curious, what have other indie hackers learned focusing on niche "mini-saas" products?