I don't believe that UA's 744's have 36" pitch in E+. The seat maps claim 34-36"; my experience would indicate closer to the former than the latter, though it could be partly UA's old style, thicker seats making the pitch seem less than it is.

Anyway, unless you're a UA elite wanting to earn the bonus miles, there is absolutely no reason whatsoever to choose UA's Y product over NZ's on the 744s. Personal space is about equal, while in every other respect NZ is in a different league, IMHO.