Market perks/bonuses to promote teamwork

[SimonFlapse]

@Jayefuu said on discord:

Anyone want to discuss some market event perks with me to replace a few of the armour and weapons choices as one off trials? 
I'm looking for things to promote team use of coins rather than single player army stuff.
1) peaceful mode. Gives players a five minute respite from attacks
2) team run speed. 10 minute buff to everyone's run speed
3) crafting buff
4) biter speed nerf
5) double damage! 1 minute of double damage for all players to help clear out an area or outpost
Etc. Can discuss balance and coin cost later.