Tag team rolls with more players

So a tag team roll costs 3 hope and lets 2 players roll each. Assuming you roll with hope, you both gain back 1 hope, effectively only costing you 1 hope, and allowing 2 players to make a simultanious attack. The book has an item that allows 3 players to tag team roll, for the cost of 5 hope. Again, if you succeed, you regain 3, effectively spending 2 for 3 attacks.

For a group of 4 players, which as far as i understand is the most common, would you ever allow a tag team roll for 4 players, and what should be the cost? how about 5?
I think it could be a little bumming to have everyone else at the table do a tag team roll, and be the only person left out so i want to hear at least what the community thinks would be the acceptable cost.

The numbers:

Looking at rolls, the chance to crit goes up from ~8% to | ~16% with 2 players | ~23% for 3 players | ~29% for 4 | 35% for 5 | 41% for 6 | 46% for 7 and 50% for 8.

The chance for everyone to roll with fear goes from 46% as 1 | 21% for 2 | 10% for 3 | 4% for 4 | 2% for 5 and less than 1% for any more than that.

Table:

Table for chance of rolling at least a certain number. The X axis marks number of players, and the Y, the smallest number rolled

|| || ||1|2|3|4|5| |3|1,4%|0,0%|0,0%|0,0%|0,0%| |4|2,8%|0,1%|0,0%|0,0%|0,0%| |5|5,6%|0,3%|0,0%|0,0%|0,0%| |6|8,3%|0,7%|0,1%|0,0%|0,0%| |7|12,5%|1,6%|0,2%|0,0%|0,0%| |8|16,7%|2,8%|0,5%|0,1%|0,0%| |9|22,2%|4,9%|1,1%|0,2%|0,1%| |10|27,8%|7,7%|2,1%|0,6%|0,2%| |11|34,7%|12,1%|4,2%|1,5%|0,5%| |12|41,7%|17,4%|7,2%|3,0%|1,3%| |13|50,0%|25,0%|12,5%|6,3%|3,1%| |14|56,9%|32,4%|18,5%|10,5%|6,0%| |15|63,9%|40,8%|26,1%|16,7%|10,6%| |16|69,4%|48,2%|33,5%|23,3%|16,2%| |17|75,0%|56,3%|42,2%|31,6%|23,7%| |18|79,2%|62,7%|49,6%|39,3%|31,1%| |19|83,3%|69,4%|57,9%|48,2%|40,2%| |20|86,1%|74,2%|63,9%|55,0%|47,3%| |21|88,9%|79,0%|70,2%|62,4%|55,5%| |22|90,3%|81,5%|73,6%|66,4%|60,0%| |23|91,7%|84,0%|77,0%|70,6%|64,7%| |Crit|8,3%|16,0%|23,0%|29,4%|35,3% |

As you can see, there is an above 50% chance that the smallest number rolled is 13 as 1 player to | 16 as 2 | 18 as 3 | 19 as 4 and 20 as 5. While there is no guarantee, and the highest number can indeed be with fear, it quickly stacks up to having a much larger chance to roll both success or with hope.

If we go by the system, you'd have to spend 7 hope for 4 players to go and 9 for 5 players to go (adding 2 each time, 1 for the raw cost and 1 for the hope they gain back when rolling with hope). Even if it is technically not doable to do more than 3, since RAW the hope has to come from a single player, who cant hold more than 6 hope, i think it could certainly be awesome to have a moment where everyone goes crazy, and let the hope come from multiple players.

However i would probably up the hope cost, to compensate for both the extra attack, and their increased chance to roll with hope / succeed / crit. Making it cost 8 hope for 4 players to go, and 10 or 11 for 5 players.