Tricky question.. I need to find examples that won't spoil too much and yet try and sell the series..
HxH is a very, very meticulous series that encourages the viewer to microanalyze with the characters, it's also can be a very ruthless and violent series for a shonen, so be warned if you're giving it to your nephew or something, I think this would be a decently representative fight:
https://youtube.com/watch?v=LHCYeIN_XgQIt gets far, far more involved strategy-wise, because the power system is very intricate with a lot of depth to it, and the fights are mostly life-or-death affairs. Be warned that this series is nicknamed Hiatus x Hiatus.. because of.. hiatuses lol, but the series is incredibly successful despite its publication issues, so there's no doubt that the anime
will return once enough manga material builds up.
One Piece is a more adventure-focused series with a focus on humor, exploration (and eventually world politics), but it has a lot of DBZ influenced-moments in there too, this is the 1st fight that got really involving IMO, don't worry, there will be villains with
far more impressive powers later on, the animation gets better as it goes too:
https://youtube.com/watch?v=9QKap4kvC4ohttps://youtube.com/watch?v=Iw3mnDMUwJABut both of these series don't really quantify powerlevels like DBZ does (:powerlevel

, which I think is a better approach because it
Oh, and how can I forget Nanatsu no Taizai? that one has plenty of fights, and a
VERY Toriyama-like art style:
https://youtube.com/watch?v=rAXTJxAVl8IIt does get a bit lewd at times though, so be mindful of that.