- 1 project manager / year.
- 1 game designer / year.
- 1-2 programmer / year.
- 2-3 months month of sound design / music.
- 3-5 artists / year.
Even if you have a great multi-skill team you need at least 5-6 people for a 6-9-12 months and it's would be very much skeleton crew.
There are cases where team of 1-3 people working part-time without funding can build a great game, but it's require both sticking to specific genres and greater use of ready-to-use assets which means it must be 3D. Game that small indie company will build in 6 month will take 3-6 years with a team working part-time.
Indie devs who self publishing only target PC because commercial porting sertvices cost starting from $10,000-15,000 per platform and it's gonna be way more expensive if game wasnt optimized for gamepad and big screens from beginning. And it's just impractical to port it yourself because it will take many months to pass certifications since know-how for proprietary platforms is not available on stack overflow.