Some thoughts after playing a few hours in Patch 5:

Another reason it would be good to remove height advantage. Bonus action hide can still provide advantage from high ground, but at least a bonus action was spent.

Currently high ground will have: terrain benefits -> Advantage -> Disadvantage on incoming attack rolls -> whatever the character chooses to with a bonus action.
That's a huge amount of benefit from simple positioning.

[I've probably mention the below before, but it feels worth reposting]

I do understand that some players are attached to the "I have the high ground" Star Wars euphoria. The easiest fix is to implement a homebrewed "Combat Advantage" from 4e, which would provide a +2 to hit. If the player gains Advantage, they would have that instead of Combat Advantage. (Of course, Combat Advantage won't proc Sneak Attack. So a rogue would have to bonus action hide to get Sneak Attack, etc.)

This way the players who are attached to Star Wars mechanics can get their fun, and the game will be better balanced. They will see "Combat Advantage" in the HUD and probably not notice that anything has changed.

This would also allow for stealth/hide mechanics to be fine-tuned more freely as a more independent system.

For fights like defending the Grove on the wall, adding in an "Elevated" status to increase the radius of ranged attacks would work (some spells still have less range than they should). The Elevated status would be independent of Combat Advantage & Advantage.
(It's rather obvious that high ground Advantage exists to help the player in this specific fight, as a lot of spells/attacks would be attacking enemies outside of normal range. It's here that the player would benefit from the Elevated status.)