After years of marriage the romance and warmth have faded into routine and duty. Is it too worldly to want tenderness and playfulness back with my spouse?
There is nothing worldly in what you are describing. Wanting warmth and playfulness to return between you and your spouse is not a distraction from faith. The calm and closeness you are missing was placed in marriage by Allah Himself, and He called it one of His signs.
See how He names what lives between a husband and wife.
“And among His signs is that He created for you mates from among yourselves, that you may find tranquillity in them, and He placed between you affection and mercy.”
Qur’an, Ar-Rum 30:21 · meaning
Two things are named there, and they are not the same. Mawaddah is affection, the fondness that laughs and lingers and reaches out. Rahmah is mercy, the kindness that carries and endures. After years together it is usually rahmah and duty that remain standing, while mawaddah goes quiet. So what you are asking for, is the half that Allah Himself put into this bond. That is not worldliness. That is acting on the verse.
And no one shows us the inside of a home better than the Prophet, may Allah bless him and give him peace. He was lighthearted with his wives, and Aisha, may Allah be pleased with her, remembered even their footraces.
“I raced the Prophet, peace be upon him, and I outstripped him. Later, when I had grown heavier, I raced him and he outstripped me, and he said: This is for that race.”
Aisha (may Allah be pleased with her), Sunan Abi Dawud (2578) · meaning
The man carrying the weight of the whole ummah raced his wife in the open, and years later raced her again and smiled back at that first race. Laughter in a marriage, teasing, play, none of it is beneath faith. It is Sunnah. What you are wishing for is waiting to be brought back to life in your own home.
He also refused to leave kindness to a spouse as some small private matter. He made it the measure of a man.
“The best of you is the best to his wife, and I am the best of you to my wives.”
The Prophet (peace be upon him), Sunan Ibn Majah (1977) · meaning
Warmth does not need grand gestures to return. Those who study married life notice the same thing: couples who quietly restart small shared rituals, a walk, a joke, a cup of tea taken slowly together, something both of you actually enjoy rather than one enduring it for the other, usually feel the closeness come back. The embers are not gone, only resting. And do not wait to be the one who is approached first. The other heart is often waiting for exactly that signal.
One small step: This week, restart one small shared moment with your spouse, a short walk, a cup of tea together, or one light playful remark, and offer it with the intention of warming the affection Allah placed between you.