Obviously this isn't a trade that's going to ring out in the history books for either franchise, but it's a bit of a head-scratcher.
Rizzo's been sending every indication that this priority is upgrading the defense, especially in the outfield and bringing in more good "clubhouse guys." Based on that, Josh Willingham, Adam Dunn, Lastings Milledge and Elijah Dukes all seem like bad fits.
Meanwhile, Ryan Langerhans seems like a particularly good fit, at least as a fifth outfielder. He's a career +18.0 UZR/150 in LF and +25.8 in right. He's a patient hitter with good on base skills, evidenced by the .380 OBP he put up in 139 PAs last year and .371 in 242 plate appearances with Syracuse this year. We don't have room for him now, but if we're about to ship off a corner outfielder or three, Langerhans would be the best choice to bring up.
Morse on the other hand doesn't provide much if anything more than we already have in Kory Casto and Pete Orr. He doesn't have the glove for the middle infield anymore, and he doesn't have the bat to be an asset at the corners. He rarely walks (career MLB 7.1% walk rate) and has basically no power (career .097 ISO power).
I guess there's some value in depth, and we don't have much in the infield organizationally, but I doubt very much that Morse could provide even replacement-level value at any position on the diamond.