Large Communities vs Mastermind Groups

I've been part of both large communities and small entrepreneurial groups. Both have their advantages and disadvantages.

I feel like small groups are aligned to early-stage entrepreneurial careers, and then larger communities are more valuable later in your career when you need access to large networks, distribution etc.

My ideal small group facilitates:

1. Accountability: I want everyone to hold me accountable to my goals.
2. Connections: I want to meet and be intro'd to interesting people, and people who I otherwise would not be able to reach.
3. Resources: People have different skills, my group should augment my skillset, and our shared buying power should unlock value I wouldn't be able to access by myself.
4. Mindset: I want the people around me to force me to think bigger and ultimately operate at a level above what I think is normal.

As an early-stage entrepreneur/builder/maker/founder, what are your top 3 most important things you want from a mastermind group?

How do you find those groups?

[Full disclosure] - I launched my first product on PH today, and I'm trying to follow an "open" approach to building it, where it's defined by what the market wants. That's why I'm asking.