Actually 6 for a 1000 is not a terrible deal, just not great. But 4 for 500 really bad.
If this mission has to stay I would also include primary objectives, count every occurence (not just the first) and make the requirement to arm/disarm/etc - no need to complete. Then 4/5/6 would be more palatable, but still the the smallest mission is pretty bad in terms of value.


