Hi Wickedghost
Welcome to the forum. Please can you be more specific about the kind of working relationships you're looking to foster with members of the forum. I also make music for libraries, so I know how it works.
What level of collaboration are you looking for? Whole songs to produce? Help adding lyrics or other elements? Please be specific. What exactly are you offering to bring to the table? (Members could just take their songs direct to publishers after all...) Also, you say that you're offering a 50/50 publishing split? Well, if you're going to be submitting to your existing contacts, they're going to take 50% on average. Which means you'll be splitting the remaining 50% with the other writer, meaning you'll each receive 25% of the publishing, correct?