What would be one of my top choices was left out of the poll: ops manager, as in. what Data and Kim did, which I see as one-part science officer, one-part resource allocation and systems management, and one-part repair specialist. I would have included that on the poll and made flight control its own option, personally. Still, from what's there, I chose operations, tactical, and science (specializing in either astrophysics or planetary sciences in the latter case).
Note that I didn't base this on what I am in any way good at in real life, simply what I'd
want to be given the premise.
I wouldn't be cut out for a Starfleet career. I'd be more suited to being a Boomer. I can see myself as owning a civilian cargo freighter.
It's interesting how what shows we've watched/grown up with/are fans of/etc influence how we read things. I've seen little ENT (and the last time I saw any was ages ago), and when I read your post, for just a moment, I envisioned
something entirely different.
Is command something you can obtain out of Starfleet or something you work into from other positions?
There's a Command School at the Academy. I might be wrong, but I've always taken it that one would sort of major/minor in the schools. A few examples:
Spock dual-majored in Science and Command. Scotty majored in Engineering and dual minored in Command and Security. Data majored in Operations and minored in Command - which is why Shelby leapfrogged him for the Executive Officer's position in BOBW: she majored in Command, and minored in Tactics. Etc and so on.
I thought Shelby was made XO because Riker wanted everyone where they were, where Picard expected them to be. Making Shelby XO threw a curve ball at the Borg's knowledge of the Enterprise and it's crew. That and her expertise on the Borg made her the right choice for XO.
You are correct; Riker told Data he strongly considered him for XO, but went with Shelby, for exactly the reasons you list here. Still, more generally,
Triumphant's idea about majoring and minoring in different disciplines makes sense, and I've always figured on something like that being the case.