Idea:
Give 1 arrow to Innocents every 10 collected coins.
When Innocent in Murder Mystery collect 10 coins he receive bow and arrow. But if they spend their arrow, they can’t receive it again! My idea is make 1 bonus arrow reward for 20, 30, 40, 50… coins, if Innocents spent it!
No this will not be fair to the sheriff
Maybe they would only receive the arrow again if they already used it before?
Hey, this is a duplicate suggestion of this suggestion : 20 Coins Reward
In the future, please use the search button before making a suggestion. 
They might aswell make everyone Sheriff
But sherrif has infinite shots, for free, while innos would have to get a lot of coins to get shots, and probably only 2 or 3 still