I think you can have two interpretations for this. One being, a dance or music. Two being, accomplish something with little to no effort. Are these two interpretations correct or is it just the former that's correct?
The word "waltz" most definitely has two meanings.
A "waltz" is a particular type of music usually with 3/4 time and the dance that's done along to it:
A waltz (German: Walzer; French: Valse, Italian: Valzer, Spanish: Vals, Polish: Walc), probably deriving from German Ländler, is dance music in triple meter, and if written, often written in time signature 3/4. A waltz typically sounds one chord per measure, and the accompaniment style particularly associated with the waltz is (as seen in the example to the right) to play the root of the chord on the first beat, the upper notes on the second and third beats.
In addition, the phrase "was a waltz" or "waltzed through something" means that it was easy or simple:
n. an easy task. The job was a waltz. We did it in a day.
in. to get through something easily. I waltzed through my comps and started on my research in my second year.
"Venus" has nothing to do with this use, though.
In relation to Cowboy Bebop, the show is highly influenced by music. It's part of the show title (bebop) and the titles of the individual episodes. Yoko Kanno's score is also a hugely important part of the show.
I don't think that the double meaning of the musical style and "easy" are necessarily intentionally used here. One of the main themes of the show is that the main characters are constantly struggling, so I'm not sure how "easy" ties into that.
That being said, some of the titles certainly have multiple meanings. For example, episode 9 "Jamming with Edward" - "jamming" means both "signal jamming" and "playing music" - which certainly coincides with the theme of the episode.