Doesn't scrypt suffer from much of the same parameter selection issues? I know I've had to choose some fairly obtuse values when using scrypt for login in a webapp.

In fact, taking a quick look again I find Argon2's "memorySizeKB" and "iterations" make much more sense to me than scrypt's "CostFactor" and "BlockSizeFactor" parameters as it's a lot clearer what's being impacted. I agree with the i-vs-d confusion, but in most cases I think using argon2id as you mentioned should resolve the contention as is already the suggested default in the IETF draft.