What you say may be true and the grain comparisons would need to be done again using the same film and scanning procedure for all.
But first I would like to produce a developer that has a stable pH using paracetamol, sodium hydroxide, sodium carbonate, sodium bicarbonate and ascorbic acid only as these can all be obtained from local shops.
I don't count sodium bisulfite used in wine-making as a local shops chemical so sulfite is not allowed.
I'm looking at Ryuji Suzuki's DS-2 using p-aminophenol made from paracetamol in place of metol and without the sulfite, although this would not be fine grain: