Welcome to the forums.
I agree with Mag and would say you should come out first and see how that goes. Developing feelings is usually something that occurs naturally, its hard to "pick" who your could partner with when they may not even be in the same hemisphere.
Coupling with couples is possible. It does and can happen, but the expectation of equal relationships is tough. Maybe metamours will be friends while there will be three who are lovers etc. In poly the key is to be open to the possibilities, try not to create too many limitations initially.
Welcome to poly, its quite a journey