If you want to get a perfect view of much of Venice, go by boat (Vaporetto) through the Canal Grande. The Vaporetto starts at Piazzale Roma (a few minutes walking distance from the Pier). The ticket for all day Vaporetto use costs 10 Euro (last year) and allows you also to go e. g. to Isola Murano (glass manufacture) or to the Lido (beach). If you have time, also a walk from Piazzale Roma through the narrow walkways along the Canale and over Ponte Rialto is marvelous. It takes less than 1 hour. I recommend to use a city map to avoid to get lost.
Enjoy Venice, it is a wonder!