Foreign Service: FSCE (Yes) = Backstop 25 (YES)
Entry Grade: FSCE (FS-4) > Backstop 25 (FS-5)
Categorization: FSCE (Specialist) "<" Backstop 25 (Officer)
Language Training: FSCE (Unlikely) < Backstop 25 (Required)
Locations: FSCE (Worldwide) ">" Backstop 25 (Worldwide)
Accompanied: FSCE (Most likely) > Backstop 25 (Not always)
Nature of Work: FSCE (Building Embassies/Consulates) = Backstop 25 (Building Infrastructure)
Both positions are in the Foreign Service, but the entry level for the State Department would be higher (more pay!) than for USAID. The win in this match goes to State.
However, USAID would give me (actually, require of me) language training, as proficiency is part of the tenuring process. That's due to it being a Foreign Service Officer position. The reason I used quotes around the Specialist vs. Officer comparison is that there are pros and cons to both, and it really comes down to what people are looking for in their job. It appears that higher status is given to the officers...but, having been a military officer, I've seen firsthand that the technicians and specialists are often the ones who get hands on with solving problems. It's that level of involvement that appeals to me more than perceived status. So I'll call that a draw because both need the other to get the job done. But USAID scores the deciding point with language training and comes back to tie 1-1.
The locations are really determined by the needs of the service. The State Department really would provide true worldwide location options, while USAID tends to focus their projects in the developing world. And because of that focus, it's more likely that I'd end up on multiple 1-year, unaccompanied assignments with the USAID job. Tough call, but State wins this round.
As for the nature of the work, it's bit of a draw: I think that USAID would probably be more personally satisfying (i.e., building a canal that provides a region with irrigation for farming) but being a FSCE would probably be more professionally satisfying (i.e., world-class facilities that play into world events). Either way, I'd be building stuff, and for me, that's satisfying.
So, the series ends with State winning out over USAID with 2 wins, 1 loss, and 1 tie. Now that I've worked through my priorities, the only thing left to do is get hired...