The Torcommunity site recently provided a datamining on the rewards for heroic quests. With the arrival of KotFE, the heroic quests of planets will regain interest thanks to a leveled reward system. Indeed, if you do this quest at level 10 or level 65, you will not have the same rewards. In addition, the rewards are also adapted according to your class.
Let me explain: if you do Heroic Quest 2+: The Chamber of Speech, on Tython, while you are level 10, you will be able to choose an equipment box that contains two pieces of armor suitable for your class. For example, in Scholar, you will have a box of Force Lord equipment. If you do it as a Guardian, you will have the choice between a Box of Wheeler equipment and one of Bulwark equipment.
If you do the same quest but at level 60, well already your reward in credits will be greatly increased, but in addition, the level of equipment boxes too! For level 60, we will be entitled to boxes of equipment from Yavin.
As long as you are not max level, but you have at least the quest level, you will also receive 5 "Common Data Crystal" which will be the new basic distinctions. Once at level 65, you will also be able to obtain these "Common Data Crystal" as well as "Glowin Data Crystal" (the new elite distinctions) or a "Locked Supply crates" different according to the quest and which will be used (in an unknown way for the 'instant) for the new alliance system.
However, there are also quests whose reward does not vary depending on the level (except about the credits which continue to adapt). These quests will always offer 4 "Common Data Crystal" and a GSI reputation trophy.
For more information, I recommend that you go to the torcommunity site which gives all the rewards for all levels of each heroic quest. Be careful though, don't try to look at the level 10 rewards on Illum's quests, you are unlikely to be eligible for these quests for that level. And remember that this is data mining, so this information is not necessarily definitive or reliable.
But if they are confirmed, I will go for a tour of the ancient planets. Not you ?