"Is the learning curve too steep to get into?"
There is no learning curve, you have new players that do not know how to play and vet players that will kill them with glee because they are free points, if the new player is feeling masochis enough, it will go to google an look for guides that will tell you that it does not matter what ship you like to fly you need to go bomber, gunship or maybe a meta scout and then suffer the process of gearing it out, while you try to get geared you still need to suffer to learn how to fly It because a youtube video isn't gonna be as good as your own painful experience.
"Is ship balance preventing you from playing?"
Its not preventing me for playing, but since the only ship i like to fly is strike fighter i find myself mostly useless in deathmatchs and only marginal useful in dominion matchs (a fully upgraded strike fighter can get one shoot by a medium gunship, been gunned down by bombers heavy lasers or destroyed in two seconds by meta scouts)
Make deathmatchs strike figthers only map.
"Matchmaking issues?"
The limited number of players may this almost a moot point, i would love to see tiers and matches were only solo players can join (to prevent pre-made slaughters, something that ground pvp should also have) and leave pre-mades fly against each other.
"The fact that GSF is character based and not Legacy?"
This is what bother me most, my main has all ships with all upgrades maxed out, my main ship have more than 400k requisitions stacked with nothing to use then in, since requisitions are comms they should be a way to transfer them to other toons, like gruond pvp used to have when it was comm based.
Also the kick system really needs a serious rework, pilots can go afk and move the ship every couple of minutes or kill themselves the full match and you cant kick them, but if you are in a deathmatch and have 5 ships on you trying to kill you and you are just skilled enough to prevent them to kill you but if you ever stop to aim are dead (so no damage done for your part) you get the kick warning for doing no damage.
May not be the place but what really annoys me with pvp in general in this game is that players can quit a game and suffer no penalty at all, while a pve player that quit or is kicked out of a group get 15 minutes lock out on group finder. even if they kick you because they want a guildy in their ride team an you have the bad luck to be on the top of gf queue list. So a player that quit a game should be penalized as well.