How much term life cover do I actually need?

Enough that, if you were gone tomorrow, your family could clear every debt and still live comfortably for many years without your income. A common rough guide is something like ten to fifteen times your annual income, plus any outstanding loans (a home loan especially), minus assets already set aside for the family. The point is not the exact multiple, it is that the payout should genuinely replace what you provide, not just tick a box. Buy pure term insurance (not a bundled investment policy) for a long tenure while you are young and healthy and it is cheap, and raise the cover when major responsibilities (a home, a child) appear. Under-insuring to save a small premium is a false economy.