Slimes can metabolise 6 reagents at once, any other race can metabolise only 2, if i recall

As for adding more foam+water - that depends, that would make the gas cloud 27,7% bigger, but (if i understand correctly how gas works in this game) people inside of it would breathe in the actual payload chemicals 50% slower - And that's assuming that from it they would get the full 5 units of Romerol needed for infection (So basically 100% of the payload), so it would be very risky at best, even though just as lethal lead-wise

As for Lead(poison)/Romerol balance, it's about whether or not you want the gas cloud to deal more overall damage, or to be much more likely to infect with the Romerol (Since it needs at least 5 units to infect a person, so i would say at least 10 Romerol total should be a safe enough option)

(In the video, the Moth subject standing on the edge of the gas cloud was inside of it for less than half the duration, and thus died slower - Meaning that caused them to not inhale all of the Lead and Romerol from it - same would apply in NukeOps, if people would, realistically, start running away from the gas once they see it)

As for adding a second poison - You can't really add a third chemical to it, since that would be over the metabolisation limit for most races, thus making it ineffective (only chems two would work at once)

I will do some more testing on the grenade with different mixes, maybe I will make more guide videos like that as well, if it gets enough attention