we are in the same situation. I get the kids to play with him and wear him out for a good.30-45Mins. I have treats i freeze and lay around, he has a kong full of different things and paste ajd another with bikkie treats. We have like a kong treat ball which i put bikkies in and throw a pigs ear out on the grass. The vet told us to get like a tyre and hang it from a tree for them to tugg at, anything to keep them “heavy lifting”.

I think with dogs, they’ll always have some kind of boredom no matter what toy you leave them. The toys become somewhat like furniture that they just get over fairly quickly. I would suggest trying to take out a lot of their energy with long walks before you leave for work so they can rest most of the day. Otherwise have you considered a second dog to keep each other company?

No matter what you put out for your 6 month old puppy, he’ll still destroy things. He’s a baby and not liking being alone. One thing you haven’t listed is lucky mats, many dogs are comforted by these