Of any of the major sports in the US that have re-started their seasons, the NBA has produced the most exciting and normal viewing experience in my opinion. While the NBA has the advantage of being an outdoor sport that isn't played in front of a large stadium full of fans and natural noise, thousands of fans are still a major part of an NBA game atmosphere. The league has done a great job at replicating a normal game experience in a couple of unique ways.
NBA games, played in two arenas in Orlando as part of the league's "bubble", have added virtual fans for each game. Above each team's bench is a large video screen where dozens of the team's fans video conference in the watch the game, engaging and celebrating as if they were actually in the arena. This has created an exciting and normal seeming atmosphere, and often fans will dress up in a spirited way or bring their pets onto the camera to add to the fun.
The NBA has also done a good job at making the game play seem as normal as possible, pumping in music as they normally would, having the announcers in the arena and not virtual. and placing advertisements as usual on the court and sideboard. After watching a game or two, you hardly notice the difference in experience in watching from home.
It's not an ideal situation, obviously, but the NBA has done a great job at keeping things as normal as possible.