I would -

Keep a few S40 'proper' phone models with a numeric keypad
Design a market-leading premium android device with top-of-the-range hardware and excellent reception. Maybe a glass uni-body? Don't tell me an android device with top nokia hardware won't sell like hotcakes
Develop mid-range phones based on the N9/lumia800/900 which run android
Keep a single maemo phone with keyboard, deb packages, gtk for geeks and developers, and see what it turns into.