I don't think that the rewards should be reduced. The thing I love about the daily missions are that it makes you want to stay in battles that you may be losing such as kill "x" number of enemies or get "x" amount of XP. If the reward system is reduced I would just leave the game as is would not be worth completing the missions. One thing though. I would take out the reward for collecting repair box drops as this makes you want to collect them even if you don't need them and so is bad for the rest of your team as someone else might actually need a repair box to heal themselves.

Hunter all the way