Well, I aim to keep things constant, so that no origins drop into weak/bland territory. For the ones that extract more, additional strength doesn’t seem to bother me if the flavour is good.
But in answer to your question, origins that extract on the lower side are:
This doesn’t indicate they’re not tasty, I really like Nicaragua & El Salvador overall & had some delicious Hondurans It’s just if brews are scoring low just because of weakness (even if balance is OK), using a bit more coffee can fix that problem (adjusting for similar extraction).
E.g. I generally prefer my coffee over 1.30%TDS. If I brewed at 60g/l a lot of my cups will land at, or lower than 1.30%, even at a good extraction.