New quests idea's

[Kwal]

That would be awesome. But I don't like the idea that only the guy killing the prince gets the reward. Too much kill-hungry people.

[Tarimoth]

Might be everyone within assist exp range who completes the quest? After all, to get there, you need to have survived 17-19th wave - that is proof enough that you deserve the reward, imo.
Not sure what the reward should be tho, a legendary is indeed a bit too much.

[Tameless]

Would be better an item which is only obtinable within the quest which is better thne normal crafted stuff but absolutly not  a legendary.