PostgreSQL is enterprise level database with transactions, full-text indexes, vector indexes, JSON, BLOB, geo-spatial data and a lot more. Highly scalable, configurable and easily maintainable. all that on an open source RDBMS database and you are still looking for GPL licensed MySQL with limited features? Look again.
trello has a much simpler interface and easy to learn for any team member. asana might have more features and configuration options but do you really need a complex system for developers to manage tasks?
After Microsoft took over trello, it has become more restricted these days but still good for startups.
Keep it simple! Focus on your product, not tools.
Sentry is so far the best in exception monitoring. It also has a decent rate limit and user limits for startups.
New relic is mostly performance monitoring but you have thousands of ways to optimise performance. With cloud based, serverless and auto-scaling solutions, performance within a limited RAM or disk space is not even a question, forget concern.