I guess like all things this must be handled with prayer. It is a tough subject to defend for too much time or too little. We must be focused on the Kingdom of God AND the responsibilities He has given us here. We can't make our family an Idol, nor can we hide behind busyness to it's detriment. I think this subject is something to handle individually in your private time with the Lord. Ask for the Spirit's conviction and the wisdom to pay attention to His prodings. There are times I miss my family so much I can barely stand to work, and times I miss the Word the same. But if my family becomes so much an addiction I no longer miss the Word, my priorities are out of wack. My advice would be to prioritize your whole life. Between my work, then the Word, then my family, I don't have time, most of the time, for much else. My work has set-in-stone boundaries of time, and it is what supports us. But at 5 when I'm done, my life prioritizes around what matters. If you are spending your time as a wise steward, and not filling it with TV, sports, unproductive busyness, then you are on the right track. With your kids (I'm guessing your realtionship with your wife is strong and growing), I say soak up every moment you can, for as quickly as it is here it will be gone. I get less sleep at night because I need my time in the Word, but I am not willing to lose my family time for an extra hour or so of sleep. I don't think there is a formula of time to use, but instead a humble, prayerful practice of love for your Great loves: God, Wife, Kids. You must desire to live your life fully passionate about many things that if prioritized correctly bring glory to the Lord. You bring glory to Him by how you love Him, AND how you love the people He has put in your care. Hope that helps.

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Dave Bishop
Laymen
Reformed, Non-denominational