As a former 2141 Reserve Marine, would 13f or 19d help push me the direction I want to go?

Its not about the MOS but about how you perform, your mental toughness and flexibility.
Can you do your job as part of the team, merging your capabilities and abilities to mesh with the other team members?

Ima give you the big facts. Forewarning: sometimes the big facts hurt.

1. 19Ds are maneuverista. That means you’ll have a clear mission set and be auctioning something semi-singular. 13Fs are integrators. You’ll be talking to multiple services and multiple platforms (indirect fire, CAS, helos, direct fire, etc) and trying to make sure everyone is safe and on the same page; more of an art than a science.
2. As a 13F, you’ll be “Field Artillery, but not really.” You’ll have to answer to both the FA and the Maneuver worlds; you’ll be stuck in the middle, and have to try and force both sides to work together. As a 19D, you’d have one boss, one mission, and one clear(er) objective. No mommy/daddy.
3. In short, if you are good at negotiation, finesse, standing your ground, and being resourceful and self-sufficient: 13F.

If you’re direct, singularly focused, like knowing what your up against, like the reconnaissance mission (and understand it), and like maneuver: 19D.