Contentment is a curious thing

A warm evening. Three interesting clients at work, a glass of sparkling mineral water, three ridiculously colourful trees outside, a brace of bikes downstairs and a freshly-scrubbed new kitchen in my great little house. I am content with life.
And ... I haven't done squat all year.
I was never so creative as when my back was against the wall and my personal equity was being shredded by bad decisions and a media slump. Gigantic information architectures, sixty-variable financial plans, a series of essays that reached a quarter of a million people. Now I'm just ... existing. Health plan, mortgage, a pension, a fun hobby and a subscription to The Economist.
A full life. A happy life. And like millions of others when they reach this point, I feel I've - stopped. Too content to push it any further.
This just won't do. Happiness is not a natural state. How do I get my drive back?