All smart TVs are limited, whether on a proprietary software platform or using a version of Android., so be careful about putting all your eggs in one basket, so-to-speak. There are some work-arounds with Android TV if the particular apps you're looking for aren't in the Sony version of the Google Play store.
Truly open Android platforms such as the Android TV boxes (4"x4"x1" dimensions) operate in the same way as any Android phone. They're a safer bet if you run in to a brick wall with a TV's built-in app service.
JVC is no-longer a main brand for TV. Most of what we see as JVC TVs are made by one of the faceless manufacturing companies that churn out the cheap supermarket-brand tellies. So whether it's Polaroid, Technika, Goodmans, Wharfedale, Hitachi, Toshiba, JVC, or basically almost any brand except Pana, Sony, LG or Samsung then chances are it came off a production line somewhere in China, Turkey or Eastern Europe.
I would never buy a main TV with a built-in DVD player. It's okay for a little bedroom TV for young kids who want to watch Pepper Pig on repeat for 3 hours while they're playing with other stuff, but not for anything larger than say a 24" screen size. Since the house is networked, buy a NAS drive and use MakeMKV to rip your DVDs. Install Kodi on Android and stream the DVDs from the NAS to the TV. If you have a BD drive in a PC then you can do the same with those. Use Handbrake to reduce the file size. TBH though, if you have kids they'll watch TV off their phone or tablet, so a Google Chromecast might be a smart move. Watch out for the internet data allowance though.
Worrying about 4K via the aerial is a bit of a red herring. There's no UHD (4K) broadcasts on Freeview or Freesat yet. Even if you pay for Sky you'll only get UHD if you subscribe to the premium football channels or download the movies. Virgin doesn't have its own 4K service yet. It is porting BT Sport content. BT Vision is the same; it's basically Freeview plus streamed content including UHD sport but not much else in UHD.
If you want a decent selection of 4K then your options are either a dedicated UHD Blu-ray player, or subscribe to premium streaming services such as Netflix or Amazon Prime.
Playing movies off a USB stick is a bit naff TBH. You've got the ability to stream from your own media library if you choose. Do that instead. You'll also find relying on the TV's own software player fraught with compatibility issues. Life's too short for that kind of hassle.