+1 to this. Leverage whatever hobby/passion you are planning to do and use it as a bonding and teaching/learning experience with your children. They will forever value it.
If you want a laundry list of things to start getting into:
- Becoming handy, teach your kids as you do it so they have that life skill. Being considered handy simply is a mindset - do you have the confidence to figure something out via some google searching etc....
- Martial arts - I took Ju-jitsu for 4-5 years and I can tell you martial arts appeals to software engineers - its highly technical which engages your brain, yet very physical which is an area we swe's hardly ever get to use.
- strength training - will increase your energy - physique - and some other passive benefits for your relationship - also something you can get into with your kids and help teach them healthy habits.
- cooking - save money and eat some tasty food - a good cookbook I swear by is America's Test Kitchen Cookbook - they cook things 20 different ways and explain why they settled on a particular approach - along with good explanations of cooking techniques