TL;DR
Quality implemented for Fluids in a freely-mixing, less-processing-blocking way.What?
Fluids would now have a Purity value.It would be treated mostly (but not exactly like) as Item Quality in most recipes.
With values of
90% Purity ~ Normal Quality
99% ~ Uncommon
99.9% ~ Rare
99.99% ~ Epic
99.999% ~ Legendary
EDIT : 0.) fluid Purity would be colour-coded too, on a non-linear gradient, for instance : 98%, 99.8%
But, unlike for Item Quality :
1.) lower Quality Recipes would still accept higher Purity fluids as ingredient :
a Normal Quality recipe would still consume a 99.46% Purity fluid.
2.) The same fluid of different Purities could be freely mixed, just like the same fluid of different temperatures can be freely mixed :
100L of 90% Purity fluid A mixed with 100L of 99% purity fluid A would result in 200L of 94.5% Purity fluid.
3.) Quality modules would work like this on Purity :
a +100% quality processing of 90% purity of fluid B into fluid C would always result in a fluid C of 99% purity :
(+100% <=> impurity (= 100% - purity) divided by 10)
90% +50% quality => 95% purity
90% +10% quality => 91% purity
95% +100% quality => 99.5% purity
95% +10% quality => 95.5% purity
(+X% <=> impurity divided by X/100×10)
4.) Quality (better than normal) recipes using fluids as ingredients would now require a minimum purity :
for instance you would now be able to make directly Uncommon quality Holmium plates (without quality modules), but they would require at least 99% Purity Holmium solution
but then you would also need to provide enough of at least 99.999% Purity both molten Iron and molten Copper to (directly, with no quality modules) make Legendary Low Density Structures from legendary Plastic bars.
5.) You would now be able to get back fluids (of potentially higher purity, with quality modules) from Recycling.
However, this would require a new "super-recycler" building :
higher tech / potentially higher tech ingredients than the basic recycler
bigger footprint (so that there is space for one input and multiple output pipes)
Basic recycler would probably still use the old recycling recipes.
(Implementing a way for the basic recycler to also use barrels for fluid output, without recycling them, seems unrealistic ?)
6.) This probably ought to be implemented as an optional modmod requiring the Quality mod.
7.) As an experiment : Speed modules would actually be allowed to lower the Quality effect for fluids into negative values, worsening Purity.
(Probably not below the "Normal Purity" 90% though ?)
Why?
This has the potential to make fluids more interesting for those playing with Quality,would allow to experiment with an alternate way of doing 'quality',
might even help with various issues, including balance ones, that Quality currently has !
Related :
Higher Fluid Consumption for Quality Recipes
Cannot make Holmium solution with quality Holmium ore
Output more fluid when using higher quality recipes (i.e. for Holmium Solution)
Have excess quality act like a durability bonus
Remove quality from items that don't benefit from it or allow "any" quality when crafting fluids
[boskid][2.0.11] Recipes with only liquid output allow Quality modules
[2.0.60] Recipes with no item ingredients do not produce quality items
Ignore Fluid signals at "Quality Transfer"
