Much like the Confederated Suns I've often mused about, any merger between the Confederation and Magistracy would, at a minimum, have to both preserve Capellan earned Citizenship and privide basic human rights to Servitors.
This isn't an impossibility. In fact, HB:HL indicates the Sun-Tzu Liao has already begun granting basic rights to Servitors, outlawing their ownership and guaranteeing them wages for work performed.
I could see Danai Liao-Centrella being able to pull off a personal union of the two States - She's intelligent, female (a must for the first joint ruler, given the Magistracy's biases), and inherently understands enough about both what is right & wrong with both states to make it work. Unlike many of the starry-eyed Canopian posters on these forums, I don't see Danai as a pure Centrella, nor as a Liao, but as an elegant fusion of both.