As for power distribution, I've never changed it. I didn't know what changing it would do, so I didn't want to mess with it.
Basically you have 200 power to be allocated to 4 subsystems. So by default, 50 gets allocated to each and that's why 50 power is considered "the average". You can allocated between 10 to 100 power. At high levels, there are various gear and buffs that can push power levels to 125 power (or more), but that's in the future for you.
Every 1 point of power you put into the weapon subsystem adds 2% to your weapon's damage. As you can imagine, going from 50 to 100 power means 100% improvement (50 * 2% = 100%).
That doubles your weapon's damage. Its a very significant increase that will allow you to destroy enemy ships much faster.
Every 1 point of power in the shields subsystem improves your shield regeneration by 4% and shield resistance by 0.02%.
Every 1 point of power into engines increases your ship's combat movement speed by 2%.
Every 1 point of power into auxiliary subsystem increases the effect of bridge officer abilities that uses auxiliary power. Mostly, its your science officer's abilities that gets influenced by aux power, but your engineer's "Auxiliary to ..." ability is also impacted.
Anyway, the key thing is you want to push your weapon power to 100% right now. That immediately doubles the amount of damage you do (well, almost doubles... there are more advanced factors at play for level 60 players, but for now treat it as a doubling of your weapon power).
None of the officers I have right now have the abilities you listed. How do I change to my new candidate?
You don't have to change your bridge officer. You can train your current bridge officer with new abilities. Go to Earth Spacedock and look for the Skill Trainer who's located under Admiral Quinn's office. The skill trainer sells Training Manuals that can be used to give your bridge officer new abilities using these not so simple steps:
1) Purchase the training manuals you need.
2) Bring up your character sheet. I normally do this by pressing "u".
3) Select your bridge officer.
4) Select "Skills"
5) Select the tier of skill you wish your bridge officer to train in. This ranges from Ensign (white), Lieutenant (green) Lieutenant Commander (blue) to Commander (purple).
6) Click on the "Learn" button beside each skill. This button only lights up when you have its training manual.
To get your officer to use his newly learned skill OR to change which bridge officer is stationed on your ship's bridge OR change the bridge officers that accompany you on away missions:
1) Bring up your character sheet again (pressing "u").
2) Select "Stations".
3) Select the station you wish to change. I am guessing for now, you only have two or three stations. As you get more advanced ships, the number of stations will increase.
4) On the right hand side, select the skill tier you wish to change. The list of skills your bridge officer has learned should appear.
5) Select the skill you wish your bridge officer to use.
Hopefully, this video should help clarify some things:
[yt]https://www.youtube.com/watch?v=_dmyQLRCtHI[/yt]