Skip, don't cancel
Make skipping a month trivially easy. Cancelling is a last resort. Low-friction pauses retain most would-be churners.
Surprise upgrade
Every 3-6 months, surprise subscribers with an upgrade or bonus. Renewal decisions aren't rational — positive surprises swing them.
Personalization from month 2
By month 2, you know what they like. Customize their box. Generic subscription boxes die; personalized ones retain 3x longer.