Hello
First I would like to say that I really like this game and I'm even more excited for the potential growth from its current alpha form.
That being said, I would like to offer a few suggestions, hopefully its something new. I think that currently the game is too easy in campaign for the player and that a few things could help even it out.
1. Its too easy to pick and choose your battles when your fight ideas revolve around clobbering a slightly weaker fleet, capping their ships, and becoming more powerful. There should be consequences for being successful.
2.Faction enemies such as the tri-tacyon, pirates and hegemony may become hostile to you, but they won't aggressively try to drive your fleet out of the system. At some point some of the system factions should get fed up at having you around and try to remove your presence from the current system. While faction relations may stay universal for every system (at least that's how I think things how things are being planned), I think there should be a level of in system, or regional "heat" for the players fleet.
I can think of 2 ways of resolving these problems. As per 1, disabled ships should really handicap your fleet. This will stop the player from jumping from one battle to another while easily escaping stronger opponents. On the system map really damaged ships should slow down your fleets movement. And for the combat map I think that having damaged or recently captured ships should remove reinforcement points since you essentially have to "baby" the really badly mauled or captured ships.
As to problem 2, I think that out of system reinforcement fleets should jump in (to hunt you), or hunting fleets should spawn at angry faction bases. Again, this should be an aspect of how big a nuisance you are in a system, not so much related to the level of faction relations you hold (although that may affect how powerful the hunting fleets are)
Some small suggestions
1. The ability to speed time to 'wait' in space or in a base/planet in order for repairs to be completed
2. No more slow down near the sun, I just don't think its necessary unless there are plans to make that area damaging
3. Separate marine personnel vs fleet personnel/extra bar on the fleet view. There should be maximums for marines on your fleet and having fleet personnel a bar in itself will give you a better idea of how many crew members you have in reserve.
4. Put a little notch, or mark on the fleet personnel bar in order to indicate the level of personnel is needed to have skeleton crews, or full crews for your fleet. This the player understands more about how his crew is effecting the fleet.
I feel kind of dirty writing these suggestions since this is in alpha, but I hope that a few of them may help refine the end product if they weren't thought of.