My favorite sports are American Football, Rugby League, Soccer. In no order really. They all have their special qualities, differences, exciting/interesting aspects.
I'm an American by birth/upbringing, but I can honestly say there's no more exciting action in all of sports than a chain-passing RL long-range Try. A great soccer goal is up there but it's usually a moment. Gridiron isn't as spectacular, but what it has is a lot of momentum shifts and drama.
I can't watch AFL, Rugby Union is ok, but not as good as RL.
Downsides...
American Football...no chain passing, blocking-centric.
Soccer....too much dead play with players passing the ball around.
RL....too much one-out, no blocking, too much caution with the ball in your own half of the field, whereas in Gridiron they often go for the big play no matter where on the field they are.
It's one area of RL i have rule ideas that could possibly help in that regard.
I remember years ago suggesting to friends that RL could use the kicking game like Gridiron uses the forward pass, to add a second dimension...and lo and behold years later we started seeing that ...players just kicking the ball across the field to an open Winger (kind of like a QB throwing a forward pass to a WR) or grubbing the ball on early tackles etc. Whereas older days it was far more cautious play.
Dunno exactly what rule, but something maybe along the lines of when you have the ball in your own 40 you can't lose the ball from a knock-on or something to try to urge teams to fling the ball about more.