GPLv3 vs MIT/Apache for an open core with proprietary add-ons

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I'm the lead developer for a small startup, and we're preparing to open-source the core engine of our application while keeping some proprietary modules closed. We need to choose an open source licensing model that protects our commercial interests but also encourages community contribution and adoption. For others who have navigated this, what are the practical implications of choosing a copyleft license like GPLv3 versus a more permissive MIT or Apache 2.0 license for the engine? How do you effectively structure the project's architecture and documentation to delineate between the open-source core and proprietary add-ons without creating friction for contributors? Are there any specific compliance tools or processes you'd recommend for managing contributions and ensuring license compatibility?