I'm too demanding, I want more than 3 things. So my personal wishlist ranked from most pertinent to least.
1. Fix all the bugs! Quest completion bugs in open world and warzones, stacking player numbers in warzones (no more 8v11 warzone matches), being able to not get DC'd so people afk in warzones. Fix the bug that lets people jump from right to mid in Civil War (it makes it too easy to defend two at once).
2. Queue as ops group. I hate only being able to pvp with a small sliver of my guild.
3. Larger warzones. Nothing crazy like 40 on 40, but 16 on 16 would be great.
4. Even out the number of medals each role can earn. Frankly a dps / healer hybrid can earn way more medals than a Jedi Sentinel. Give medals for assists in Huttball, attack players near a gun battery when it was captured, etc. While we're at it, maybe give some valor extra for actually voting for MVP, that way you not voting means you are personally missing out.
5. Fix the faction imbalance. How? Allow for people to queue as a "mercenary" and fight on the enemy side for extra rewards.
And not a change, but keep it the way it is:
6. Don't add a debuff for leaving a warzone early. They already get nothing if they leave early (valor, commendations, etc). If you don't want to be in this warzone with me, leave! I'd rather take my chances with the next guy in queue than know I'm stuck with someone who doesn't want to be there. Forcing them to stay means they are more likely to not try / or dawdle around. They already decided it was going to be a loss.