I think overall it sounds ok! He likes Minecraft, so I'm guessing he'd also like Legos, K'nex, building things. He plays well with friends, so let him have lots of playdates. He likes Spongebob, which maybe isn't terribly academic but my kids have always benefited (jmo) from having a cartoon they loved that they could relax and laugh at. Really he sounds like a typical and well-adjusted 4.5 year old boy.
Long before my oldest was much more than 3 I had this vision of no electronics ever for entertainment and having all sorts of cool arts and crafts projects and science experiments etc to entertain my kids. I'll admit I was not rolled at all when my ds discovered Minecraft! But it turned out to be a phase, and it also really did provide him with a lot of fun creating his Minecraft things. I am not sure you'd want to know what replaced Minecraft, but he's gone through a series of two other computer games that are similar in that they involve building and creating and honestly, they are pretty darn cool and definitely more mind-stimulating than the computer games I like to play lol. We limit his screen time and he has other things he enjoys doing, but really none of my kids have ever spent much time doing the projects I'd picked out for them - they tend to find their own! FWIW my Minecraft ds loved K'Nex and Legos at your ds' age. He also used to just build things out of Inge that weren't toys - just things and the house. Later on through school and clubs he became really interested in robotics and things like that. Actually now that I think of it, he wasn't much older than your ds when we got him a Legos Robot kit.
Anyway, I'm not sure there's much to be concerned with. If you're wishing *you* had more play time with him, does he like to go on hikes or Nike rides etc? Those are some of the things I do with my ds.
Best wishes,
polarbear
