Then Israel is deliberately bombing homes, schools, hospitals and health centres - (you have the figures for the latter three) - which is a war crime.

It would be if it was indiscriminate, but it is not.

Re flechettes.
Most weapons are intended to kill and maim by driving bits of metal at high velocity into and through people.
That is legal and includes flechettes.
Any such weapon can be used illegally.

All Hamas sites are placed among civilians.
That does not mean that Israel is forbidden to defend itself from their illegal and indiscriminate attacks.