You did U-smash -> Force Palm at least once. Therefore, your Lucario knowledge is already vaster than mine.
Usually at low percentages I will attempt a Dash Attack > U-Tilt > U-Smash > F/U/N-Air. (Fun air? Seems legit.)
At higher percentages I do Dash Attack > U-Tilt > F/D-Smash. But it seems this is really easy to DI out of.
Sometimes I will do Dash Attack > D-Tilt > F-Smash but mostly I don't rely on D-Tilt.
The site shows Dash Attack > U-Tilt(?) > U-Smash > F-Air > Side-B, but I've only been able to successfully do that offline.
U-smash is also jump cancelable. I find that character really hard to play online. I know Tatsu kills at around 100%, so I'm curious if you can Shoryuken -> Jump Cancel Tastu to get a quick finisher. I'll have to look more into him.
Huh. So it is possible.
Personally I find U-Smash > Jump > Side-B more effective, because timing the Side-B transition from U-Smash incorrectly looks punishable.
I did that with Lucario one time.