I myself am no where near 95 mission completions, but I do have an idea on what you can do for those who do get that far.

Dark Matter Array

Increases attack by 50, Defense by 50, and cloak by 50

If scientist it also adds 50 to research points overall

If (Insert research race here) adds 50 to research

If (insert battle race) add 10 extra attack and 100 planetary attack points

If (insert Hack race) add 10 to cloak and +10% hack bonus

If Miner add 100 to planetary attack

Or you could make it one of the bought epic installments

+1 to have more tier rewards(especially as new missions are being added, there should always be one every 5 missions until all mission run out)

But ur module is too much
The 50 atk, def and cloak is enough already, if not too much~ I would personally say +30 to all those 3 would be sufficent
but a racial/class based function... that's interesting and can become the 100 one after maybe a bit of boost etc

we need more mission tier completion rewards ....

Yes even if there weak mods , as long as there still 0 space , I think it would make everyone happy.
Or you could just reset the list with higher mission completion's needed.