It's nonsense that you can't do much with Beavers. We've recently been on a full group camp, and the beavers did (almost) everything the older kids did, just with more help. They pitched tents, cooked on a fire, did crafts and climbing, archery and water games. All in an age appropriate way, but they did loads.
They hike, cook, and play games, they do pioneering, visit fire station, tie knots and learn about their promise. Beavers are a lot of fun! (and I say this as a cub leader)
Exactly this, beavers have a blast and you can do most things with them, they learn so many skills.
We took our squirrels for the day on a camp day, they loved it, they were all pretty well behaved and really enjoyed it. Of course you need good ratios for days like that, but our squirrels do lots of excursion and during the session we go exploring, toast marshmallows, play loads of games, it's great