I am really staggered at the reduction in seats it must mean leakage to other airports. Monarch a great loss to BHX, and the end probably of the long run of impressive growth. BHX-AGP needs 2x daily even in the winter.
But on the other hand ensured the carriers that remain are making good (proper) yields. It would have been low yields that did, at least in part for Monarch.
Sometimes enthusiasts are too quick to look for new services / increased capacity / higher passenger figures without considering the business consequences.
That said in the case of BHX/AGP it has been a bit of a case of famine to feast to famine. A happy medium (and you don't find many happy mediums!) would be preferable.