If I remember, it will be a Tier 1 skill Technology skill. It competes with Sensors. Player has a choice between Transverse Jump or Neutrino Detector on the skill tree. Alex might have wrote that the abilities would also be unlocked another way, probably a quest. As for me, Navigation would be the no-brainer choice over Sensors. Hopefully, there will not be needle-in-haystack pirate bases that are impossible to find without Neutrino Detector.
As for OP, I lived without Navigation for a long time, trying to eek out more skill points for combat, and the experience is painful and unpleasant. Eventually, I took it and I agree with the others that it is a must-have skill, even if it is useless in a direct fight. Without Navigation, fleets drink up lots of fuel, so player might need to bring another Prometheus to support his endgame fleet. Burn speed is important when the sector is burning down. Navigation lets player dump two tugs or Augmented Drive Field. If player has a game where a pirate base respawns repeatedly in a neutron star, Transverse Jump can let the player avoid pulsar beams, or at least not cross them twice per visit. Finally, if your home colony is in a big system far from a jump-point, being able to T-Jump out of the system instead of spending in-game days traveling from planet to gate is nice.
As for most powerful skill, my vote goes to #1 Electronic Warfare 1, #2 Loadout Design 3, and #3 Fleet Logistics. Electronic Warfare 1 as defense against enemy fleets with EW1. The alternative of cramming ECM hullmod on all of your ships is very painful. Loadout Design 3 makes your ships less OP starved. Fleet Logistics has too much useful stuff in and out of combat. I like the ship recovery with officers so that Reinforced Bulkheads is not necessary.
Officer Management varies by fleet composition. If the most the player can fit is three Paragons, player can get by without any. If player can consistently cram eleven ships in battle, then sure, Officer Management is must-have. Personally, I would like at least 1 in Officer Management.