Things to do and where to stay in/around Yosemite?

Since you're not pressed for time I would recommend seeing the other side of the park that very few get to see the hetch hetchy side. Unlike the main part of the park there is no development there is no gas stations and hundreds of tourists. It's absolutely gorgeous. Nice easy hike to Wawona Falls through the tunnel on the other side of the dam. With all the rain lately & the snow fall this year the falls should be absolutely epic. Evergreen Lodge at the entrance to that side is a nice place stay or chow down if you're hungry. You don't have to pay twice to get in either.

As you probably know if staying in the valley, get your rooms now.

Drive over the Beartooth Pass, stunning views

Are you sure camping is out of the question? The pines campground is an awesome place to wake up and go to sleep every day. You could rent an RV or small trailer to stay in. There is a pretty decent bathhouse at curry village so showering is not that big of a deal.

No tips as far as sleeping goes, I usually just bounce around to whatever campground I can get a reservation at each night or camp on the trail. But if you didn't last time, you should check out Glacier Point, one if the best viewpoints in America in my opinion, high elevation panoramic views of all the highlights in the valley, El Cap, Yosemite Falls, Half Dome, Vernal/Nevada falls, etc. If I were you, I would catch a shuttle bus up to Glacier Point in the morning, then take Panorama trail back down to the valley floor, I think it's about 9 miles, but mostly downhill. It leads to the top of Nevada Falls, then you take the Mist Trail (or the John Muir trail if you want to avoid the granite stairs) down, so you'll pass by Nevada and Vernal Falls on your way down and never have to deal with climbing up those million stairs, then you can hit up the pizza joint in Half Dome Village (formerly curry village) when you get down!

Going up to the top of Yosemite Falls is great too, but only if the family is up for a 2,600 ft climb! You could also spend another day at high elevation up near Tuolumne Meadows, lots of cool features up there with less crowds, and if you want to see big trees, the Mariposa Grove of giant sequoias was just reopened after a trail facelift, in the south of the park. I wish I lived closer so I could spend months there!

On the panorama trail and from Glacier Point

https://www.mercurynews.com/2019/02/03/insiders-guide-to-yosemite-everything-you-need-to-know-about-the-park/

https://www.mercurynews.com/2019/02/03/yosemite-family-adventures-in-renovated-mariposa-grove/

I also recommend Glaicer Point. I rode my bike from Fish Camp to GP last year and it was epic.