I don't even really use it for that. I have a kitchen timer on my microwave and another one on the oven. Both are easy to set. I can see if they're running and how much time is left.
I'd guess that half our Alexa utterances are for setting timers (the other half being split between listening to music and summoning the family to dinner/other announcements). Having dirty hands or not having to walk over to frob buttons makes the voice-activated timers pretty compelling to me.
Both my kitchen timers are sealed panels, one above the stove and one on the oven so I guess I just got in the habit of using them years before I had an Alexa.
I don't really even use the small one in the kitchen except to ask for a weather report now and then. But I see how the timers can be useful. They're very handy for my dentist etc. and would be for timing anything when you really don't have a free hand or want to touch anything.
Bedroom is light and alarm. Sometimes music but I don't really listen to music in bed. Downstairs I play off the AppleTV connected to my stereo system.
Set timer, play music, turn lights on/off, get weather report accounts for 100% of my Alexa usage. My wife uses the summoning function occasionally and my kids used to ask it random questions when they were younger, but yeah, that's about it.