Personally, I wouldn't get anybof them for end-game.
The 2015 Harvest pack has a good mid-game bonus of Protector 2 at Legendary but that's it.
Treasure Hunter 2 is ok for extra quest bits but there are others that you can use just as easily.
Healer 2 at end-game may or may not be useful. There are a lot of people that aim for 100% revive/energetic teams meaning no healing needed. Others stay with 90% healer/100% energetic for minimal downtime.
Ultimately the choice is yours. I would advise going for the Giant pack for a Support 2 Sword which is exceedingly useful or Hero 1 pack for Support 2 Gloves...
Mayor of Elysìum (rank 191 Nw)
Lvl 51, 122.1G Nw, 451/559 BPs mastered.
All wood/leather/iron/gold BPs.
4 Magic. 3/44 Primal.