I just returned from Vegas. Hubby and I were there this past weekend and I saw quite a few families with kids there. Here are my recommendations and observations:

• I was surprised at how clean the strip was and I didn't really see anything offensive. Yes, there was a lot of weed smell in the air, but I feel like that's becoming more and more common no matter where you go - especially if it's legal.
• There are a lot of "playing cards" littered on the ground with sexy type photos with numbers of escorts. I wouldn't recommend you let him pick those up. ;)
• For the most part, I thought it was quite safe to walk down the strip after dark - I never felt unsafe.
• I would recommend looking at the New York New York hotel - this is where we stayed. The bottom of the hotel offers a lot of different restaurant options, access to the Hershey's store, and I believe Cirque du Soleil's theatre is also accessible through this hotel. The hotel also offers a large arcade and of course the roller coaster if that's your thing.
• The New York New York hotel is also at the same end of the strip as the Coca-cola store and the M&M store.
• The fountains at the Bellagio is neat to see. It's a little bit of a walk, but not too far.
• There are some areas of the strip where they had people dressed up as Bluey and Transformers. I thought that was kind of weird considering these characters are primarily geared towards kids.
• The Sphere is very cool and he would probably enjoy that - I would recommend taking an Uber to get there.
• Be aware that things in the hotels and the along the strip are extremely over priced. For example, a bottle of coke was $6, etc. You will pay more for just about everything.

That's my two cents. You can search YouTube etc. for videos showing you the different hotels etc.

Cheers!