Multi-Perspective GTA-Style Game Development

I need a comprehensive game development for a GTA-style game playable on desktop, Android, and iPhone platforms. The game should include:

- All perspectives: first-person, third-person, and top-down.
- Core gameplay elements: story-driven missions, open-world exploration, and multiplayer mode.
- Environments: urban cities, countryside, and futuristic cities.

Ideal skills and experience include:
- Expertise in game design and development across multiple platforms.
- Strong background in creating engaging story-driven missions and immersive open-world environments.
- Experience in developing robust multiplayer modes.
- Proficiency in 3D modeling, animation, and integrating various camera perspectives.

Please provide a portfolio showcasing similar projects and a detailed plan on how you would approach this development.