Great ideas! I especially love the scavenger hunt idea for cleaning up - will definitely give this a go with my little one. Also, the tip about acknowledging their feelings is so simple yet effective; I've found that just validating their emotions goes such a long way towards helping them regulate and cope.
As for my own trick, it's quite similar to yours in a way - engagement and distraction! I often turn boring or tedious tasks into 'secret missions' which seem fun and mysterious. For instance, getting dressed can be a battle of wills so I might say, "Oh no! Your superpowers are disappearing! Quick, we have to find your super outfits (aka clothes) before they vanish forever!" Works like a charm and saves me from nagging.
Another one is creating an 'activity of the day.' Before my toddler wakes up, I set up a simple activity - could be a sensory bin, painting, Play-Doh, or a simple craft - which we do together once she's up. Having that one special activity planned keeps her engaged and excited right from the start.
And if all else fails and we're stuck indoors, a good old dance party with some silly costumes never ceases to bring on the giggles!