Couple of thoughts. First, my understanding about the SWO "blue chip" issue is that it works both ways. If the ship AND the mid like each other, the mid can get that ship. However, if the either wasn't fully satisfied, the mid can/must choose a different ship.
As for service "selection" (in my day) or "assignment" (today), not sure the change is as dire as it seems. First, in the past, "selection" was based on your OOM and your vision. Thus, those with great eyes in the bottom of the class often had more options than those with bad eyes who stood higher. Second, when your turn came, you took what was left. Thus, if you really, really wanted to be a Marine and were really, really suited for it but stood too low in your class, guess what? IOW, just because you got to "choose" doesn't mean you received your "choice," although I'll grant that you did get a choice of what was still left.
Third, today there are "screeners" and first class cruise options that help both the mid and the service decide if it's a good fit. In our day, a LOT of folks went USMC either just to fly (wanted to be pilot, no interest in the Marines) or went SEAL/EOD with no real prep. While some of these folks did well in the long run, a lot more did not. Today, there is more of a "matching" process that should result in young officers who are more suited for their chosen fields and thus hopefully happier and more successful. Fourth, the nuc draft existed in our day. Rare but it did happen -- so now it's the NFO draft. There will always be jobs that are perceived as "less desirable" and they still have to be filled. In that vein, welcome to "needs of the Navy." It is something that will hit again and again and again and most of the time it sucks.
The bottom line is that it's not as if mids in my day had a 100% chance of getting their first, or even second, choice. Yeah, the folks at the top did but once you started to hit the middle of the class, all bets were off. And, I'm not sure as much thought/preparation went into the choice as happens today. It's really too soon to tell whether the new process will result in happier jr. officers and less attrition -- only time will tell.