Following are the top 20 things that I have come to learn over the years that I feel, if implemented, taught, embraced, and adhered to, will be the keys to maintaining a happy and efficient home, as well as a posterity fully prepared to go forth and do likewise.
Feel free to add to this list in the comments! :)

1. Every person in your home is entitled to a safe, drama-free environment. Make this precept the primary goal in all things. Make NO exceptions to this rule. When an individual chooses to disrespect the right of others to a drama-free environment, that individual must "repair what they broke"; make it right, make reconciliation with whoever it is they have affected and offended. It is the RIGHT of all members of your household to peace. Defend those rights, to one and all.

2. Teach your family NOT to waste. Electricity, water, heat, food, AC...only use what is needed, then TURN IT OFF or CLOSE IT. Frugality is of lifelong benefit to all who learn it.

3. Consider every situation, moment, and interaction as an opportunity to teach your children. Drop a bit of relevant wisdom, point out something of interest, show them affection, do something that you would want them to mimic, ask them questions to get them thinking, connect a dot or two, etc. Just always be mindful of the fleeting time and that one of your primary jobs is to guide and instruct, whether by word or example.

4. Every rule you have set for your home should be upheld at all times, without exception. Consistency is so very vital to maintaining a happy home.

5. Consider every rule in place a guide, and treat each violation as an individual situation, applying judgment and love. The true goal, desired outcome, and primary reason behind having rules is that, in the end, you will provide your children with a stable and consistent environment, and to instill within them the ability to discipline themselves. Do not make the mistake of enforcing rules without making judgment in every individual situation the lens through which you consider the circumstances of the matter. A child's age and maturity level, their ability, capacity for understanding, motive...all must be weighed. Use the rules as a starting point, a guide, by which to assign standards to your household; but in all of it, use judgment first.

6. Taste life. Life happens each and every moment, but make it a point to purposefully taste it, be aware of it, appreciate every small thing. This is for you personally, first, then for your family.

7. Make it a point to teach your family that there should be moderation in all things, at all times; that too much of anything (tv, fun, food, video games, sunshine, sleep, work, laziness, etc.) can be detrimental to one's well being and mental health. Practice what you preach, and point out to them the times when you and they DO exercise moderation and how much better it is.

8. Hold your children accountable for their actions. Reward those that are good, punish those that are bad, always mindful to exercise judgment in the situation based on the child's age, the situation, the circumstances, and the child's maturity level.

9. NEVER reward bad behavior. NEVER.

10. Be consistent in the manner in which you apply the rules and guidelines of your household. No favoritism, no slacking due to your own apathy, no double standards.

11. As often as possible, spend the first few minutes of bed time talking to your children. About your own childhood, Bible stories, analyzing situations that happened that day, making shadow puppets on the wall from the streetlight coming in the window...anything. Spend that time with them, make it special, make it memorable. Make sure they know that they are loved.

12. Start family traditions. Even small things will stay with them and their children for generations to come. For instance, my grandpa used to take me out to sit on the front porch with him, and together we would eat an apple. he would peel it and give the peelings to me, then take turns cutting slices off of it, one for him, one for me. During that time we would just talk about things...those times were some of my best memories, so I do it with my own children and grandchildren. Nothing is too small to be special.

13. Expose your children to new things. New genres of music, new leisure activities, new games, new books or movies; teach them to desire the expansion of their own horizons, and how to do it themselves.

14. Teach your family to respect nature and the earth. Never allow them to throw their trash on the ground, don't permit the pointless killing of any living creature for no reason, relocate spiders that find their way into the house by catching them and releasing them outside, teach them to be mindful of recycling, put a bird feeder on the back porch, plant a small garden (even in a flower pot!), set up a fish tank, and any other thing you have opportunity to show them by your own example.

15. Show the children, consistently and without fail, how to respect and love their mother. Show them this by your own love and respect for her. Never permit even the slightest hint of disrespect from your children toward their mother, and always rise to her defense when such things occur. Stand by her side, unwaivering, and show your young ones the queen that their mother is. In this they will learn how to treat women, how a child ought to esteem his or her mother, how to behave themselves well, and how to become respectable people themselves.

16. Teach your family not to fret during times of apparent financial stresses; be the pillar on which they can lean. Maintain a positive attitude, a proper prioritization of the things life consists of, and demonstrate the benefits of being resourceful, shoring up the budget, selling unneeded 'stuff', and being frugal in order to meet your family's needs. When you have finally run out of things to do and try, take the family for a walk. It helps clear the mind, relaxes the body, and I can't count the number of times I have done this and come across some idea or means of meeting the need (an unexpected check in the mail, finding cash or (back in the day) a book of food stamps, etc.). Show them how not to fear those things outside of our control, and instead to count their blessings and have faith in one another and that omniscient presence that sees all.

17. Never assume that by nature you will always love your wife like you should. It isn't a sign of weakness or fault in the relationship if you would benefit from some proactive soul searching and self-reminding about why you chose this woman and she you. Find scriptures that speak of the love and fidelity of a husband toward his wife, and lay them to heart. Get them out every now and then and read them, think about them, remind yourself, renew your love for her.

18. Even if you are a man who could hold a grudge for ten lifetimes, at the very least you must ALWAYS keep the door of forgiveness open to the truly repentant. If a person truly sees the error of their ways and asks you to forgive them, it is your duty to do so. Make this a part of the man you are.

19. Practice self-sacrifice for your family and for others. Not to be seen, so much (though that will occur sometimes), but for your own sake. When there is only enough pancakes left for each of the kids to have seconds, serve it to them happily, no matter how much you wanted one too...you can always go back later and grab an apple or a bowl of cereal if you're really that hungry! When everyone is in line for showers, go last; when you see something that you know your wife usually does (like take out the bathroom trash, or get up early and get your son ready for school), YOU do it. Every act of self-sacrifice, even in the small things, will make you just a little bit better man.

20. Make it a point to execute random acts of love and kindness...special acts...toward your wife. The unexpected back rub, breakfast in bed, a carefully chosen piece of jewelry bought on ebay, doing the dishes, INSISTING on date night, showing up with two glasses of chilled blush, your best attempt at poetry...the random, sincere "I love you"s; These are the water that keeps the plant thriving, the logs that keep the fire burning, the health that keeps the hearts in sync and beating.