Well here it goes, my two cents...
Is the learning curve to steep to get into?
Yes! I played for a year before I found out about the F keys, as an example. I must have missed that part in the tutorial if it's there. Additionally the tutorial is not a good example of how GSF actually works. Allow 1 vs 1 matches that will allow people to go at each other if they want as well as allow a person to help teach a friend. Understanding how you should build your ship can take some time as you have to read what each thing will do for you to make up your mind what you want to do.
Is ship balance preventing you from playing?
NO! I play, but the ships are balanced from what I can tell, other than the strike fighter but you know that already. I suspect that it's the pilot skills that are unbalanced.
Are you not playing because you feel GSF needs something new to bring you back in?
I play, but I do feel that GSF needs a few things like...
The ability to have 1 vs 1 fights. This would allow people who want to do GSF when it's not popping to pair up and fight each other. A better way to get rid of players who are just sitting around. Allow 1 person to vote them off if they are not contributing and have less than 2K damage done, 2 if they have less than 3K damage, and 3 if they have 3K+ in damage. This would allow players to be removed easier if they are just sitting around to get their daily done. Random asteroid and structure creation so the map is different to a degree, even if the sats are in the same place. Allow for smaller groups to play a match using the que. 4 vs 4 would help get more pops from the que, this may require smaller maps to pull off. Let us use ship req to purchase cosmetics per ship. I can understand needing fleet req to purchase a new ship for your fleet but when you want to change the cosmetics on one ship you should be able to use ship req. I don't care what my strike fighter looks like, I don't fly it and I have almost 2 mil in ship req on my GS.
Matchmaking issues?
Frankly matching is what it is. People complain about premades but the bottom line is that even if you forced everyone to que solo they would still be using voice chat to organize and that is what makes it hard sometimes. Do not allow ops groups to que as one team or that will be messed up. If you had 12 people all in the same chat room using voice the other team would not stand a chance. All ops groups should be split and forced to fight each other.
The fact that GSF is character based and not Legacy?
No thoughts here....