I made a big list adding together all the rewards you can get from the campaign, based on the previews.
Normal Rewards
8750 gold
3780 soul
490 glory
32 gold key
18 glory key
4 gem key
2 event key
90 Minor/Major Traitstone
34 Runic Traitstone
30 White Pet Food
4 Epic Ingot
16 Treasure Map
680 Gem Shard
40 Chaos Shard
Elite Pass
25000 gold
2250 soul
290 glory
90 gem
830 gold key
32 glory key
12 gem key
8 event key
30 Runic Traitstone
12 Arcane Traitstone
120 White Pet Food
180 Colored Pet Food
375 Common Ingot
5 Rare Ingot
2 Ultra Rare Ingot
1 Epic Ingot
1400 Gem Shard
400 Chaos Shard
20 Coin Purse
10 Gold Ring
4 Priest’s Chalice
2 King’s Crown
4 token of gaard
3 token of yasmine
2 token of orpheus
1 token of aranaea
Mythic Pet
Epic troop to Mythic
Heart of Rage
Mythic Troop
2x Weapon
Cosmetics
Elite+ Pass
15000 gold
1500 soul
290 glory
120 gem
40 gold key
16 glory key
9 gem key
4 event key
1 vault key
Overall it seems like the value from campaigns is almost all in the big ticket items, those being the artifact for the normal pass, the Mythic for the Elite Pass, and getting artifact levels earlier/more easily for the Elite+ Pass.