T.M.
It's kind of like the "terrible twos".
Best thing to do is support his "ideas" but then show hime the facts.
Buy him a little bucket to put his thoughts in.
You dont say how old your husband is, mine didnt start feeling "entitled" till he was 50. I would listen to him, we would talk about his "fantasies" but were able to squash quite a few of the totally unrealistic ones.
Men's egos put them in a difficult spot with their peers as far as "success" goes. Tread lightly, dont squelch his spirit if you can help it. Do try to make some of his little dreams come true when you can.
Kids will grow and be gone one day.... they will have their bucket list too. (Dont ruin your adult life trying to do things for your kids ALL the time, kids are temporary)
You guys are grown kids and trust me, you will soon have a few things on your bucket list as well.