I have a bit of the same dilemna: I don't like to waste tea. Since, contrary to supermarket tea bags, there are at least 3 steeps per batch of leaves, I feel compelled to have many cups (each cup about 100 ml that is, not mugs !). And sometimes, like in the morning right after breakfast, I really want to have only but one cup.
So now I'm experimenting with brewing less leaves but raising steeping time. I'm doing this currently against established beliefs, eg. I'm using a 150ml yixing teapot to brew a small batch of this year's Yunnan Mao Feng (current breakfast tea). And so far I'm pleased with the results. Tea leaves are not much and taste is there. I steep it for about 2 minutes. Next step will be reducing the leaves further.