While I appreciate the suggestion, the fact is that no machines in Factorio works that way. I base how I balance mods on the base game, and every machine with multiple tiers always lowers pollution for the higher tiers, at the expense of increased power. The only upgraded machine that doesn't do this is the Steel Furnace, which has exactly twice the pollution, fuel consumption, and speed of the Stone Furnace, and exists solely as a space-saver.
That said, thank you for the kind words. If I make changes going forward, I will keep this in mind