As a talentless father of talented kids, the one and only bit of advice I can give is get the thing they dig, they'll be more likely use it. Son with his guitars and daughter with her bass both played astronomically more once they got nicer instruments. Motivation is a factor, just like with our bikes. If they can't walk past it without reaching out for it, they'll play and play and play.
100%... although I think every guitarist should have a decent acoustic, if you don't last through the initial stage of learning, to keep playing, then it is irrelevant if you started on an acoustic/electric or not. So, if they want an electric, go for it.
If you can, get someone to set up the guitar properly for your son. A high action is no good for young hands.
Also 100%.
Back in the day, I paid a local guru to setup my guitars and it was totally worth it. But about ten years ago, surfing the net I discovered a website that described the process really well, with great examples of various styles of setup, and he used feeler gauges (not a fricken steel ruler) to do the measuring. That was enough for me, as I knew (with feeler gauges) I could accurately repeat the process, and move forward. Nearly all guitars can benefit from some form of setup. It is really like tuning the guitar to the player. A players light touch or heavy handed approach will determine how to setup their guitar.
Setting up a guitar involves measuring and adjusting four things... neck relief (how curved the neck is), nut slot height, saddle/bridge height and intonation. With careful measurement and the right tools, you can often transform a dog into a very playable guitar, and at least marginally improve an already good guitar. While you're at it, a fret polish will be like icing on the cake. I've done all of my guitars and basses, my daughters guitars, their boyfriends guitars and basses, and an old bandmates guitars. All of them were improved after the setup, some more than others. I've got a few backed up to do yet, but have competing priorities.
I think the going rate for a setup is less than a $100, so if you are gonna stick with playing, it's worth it.
This is my handmade cedar over koa from Saigon. I've done three setups on it, over time as it acclimatized to Oz weather. Everybody who plays this guitar is blown away... as it play like an electric with 9's. This one comes to the nursing home with me.