The Xbox One X is the best console I have ever owned in my entire life. And the hate it gets is unwarranted. People harp on the fact that PS4 has more exclusives, and that it does. But Xbox has spread out exclusives to dominate a few key genres that Sony doesn't. Like racing games, platformers and shooters. Those 3 categories all go to Xbox. Not to mention Xbox performs 3rd party games much better than the Pro does. It balances elegance, UI with flawless 4k graphics and visuals. It has the greatest controller I have ever held. It took everything I loved about the 360 and upped it 100x. It is dependable. I have put over 100 DAYS into my original Xbox. And probably a few dozen days into my One X. They are just amazing
As for your questions.
1. You need internet to play most games now. But you can play offline without the xbox gold. You will just not be able to play with any multiplayer online features or use chat.
2. You do need to download most games from the disc even when you buy digital games. They are downloaded and stored onto your HDD. If their is a way to avoid it, i'm not aware of it.
Are the modern consoles worth the money? Well old gamerz, I wanted to let you know that Xbox One S, Is going to be on sale black friday for 149 at Walmart And One X (the king of all consoles spec wise) will be 349 with Gears 5 bundled. So now is the best time than ever to buy one. I'd say not to spend too much because Xbox Scarlet will be here next year. But they are well worth the price tag imo
Enjoy!