I use some Avios to discount SH J tickets to make them more akin to Y prices. This isn't necessarily the best bang for buck, but I do it in part to 'buy' status. I travel more by myself in SH and LH with others (usually in Y), so when I'm taking the latter flights it's nice to have the status benefits making it a more pleasurable experience.

For redemptions, you'll find far more expert views than mine, but I do also keep some Avios aside for that and to make decent use of the Amex 2-4-1.