Bad idea IMO. Keep your friends close and enemies closer. Despite some tangled representational interests were we to toss the feeders to their devices to get representation I think you would end up with a whole lot more pilots a lot more vocal about flying bigger aircraft with no Scope conflict of interests in doing so with their former ALPA brothers. Worse yet you might end up with ALPA as the final arbiter for a lot of RJ carriers going against your one off in-house. While perhaps pie in the sky I think the solution lies in working within ALPA at raising the wage and cost gap (in the RJ favor) to make eventual integration with their mainline partners feasible. While perhaps well meaning splitting ALPA plays directly into managements hands.