Just make alchemy products multiple use. Stimm-slugs are infinite, why shouldn't escher stimms be the same? While Stimms-slugs can overdose you, escher stimms require an action to use, which is a fair trade off.
If something is too powerful from becomming infinite, such as Night-Night, add an exception for that chem/toxin that include that particular effects, they remain one time use due to exceptionally powerful chems having unstable formula which fizzles out quickly after they got synthesized. I guess you could add a motivation to mix it in by giving it an additional use for every non-unstable chem added into the mix (so a chem:night-night+wide eye is removed after 2 games).
Alternatively, Night-night in the mix fizzles out after 1 game, so chem:night-night+wide eye becomes just a wide eye after 1 game.
If something is too powerful from becomming infinite, such as Night-Night, add an exception for that chem/toxin that include that particular effects, they remain one time use due to exceptionally powerful chems having unstable formula which fizzles out quickly after they got synthesized. I guess you could add a motivation to mix it in by giving it an additional use for every non-unstable chem added into the mix (so a chem:night-night+wide eye is removed after 2 games).
Alternatively, Night-night in the mix fizzles out after 1 game, so chem:night-night+wide eye becomes just a wide eye after 1 game.
Escher were the worst gang in GoTU due to gangers uniquely having CL8.You don't need to fix House of Blades, just use the Gangs of the Underhive list...