I found it strange that mercs with high explisive skill, like 90+, throw grenades as bad as mercs with low skill of explosive. I have Barry and Meltdown in my team and they are both have high chances of failure when throwing grenades even though Barry has 90 exolosive skill and Meltdown just 40 but sometimes Meltdown throws grenades effective than Barry just because she got lucky with random. I think it's unfair for mercs with high explosive skill.
I suggest maybe reduce a liitle chance of failure the higher explosive skill of merc, so for example mercs with 90+ explosive skill have medium chance of failure and not a high when throwing a stick grenade. Grenades will still be random and you need to guess where grenade can launch but mercs with high explosive skill have a little advantage and it will be more fair for them.
I am still on starter island so I didn't tested a lot of grenades in game.
Btw I am really enjoying your mod. Your mod + better enemies + max difficulty gives completly new experience.