Venice Tickets into Basilica and Doge's Palace

Absolutely. There is seldom, if ever, a line there.

Note that the Combo Ticket is not related to the Basilica visit. The Basilica is free, with usually a line to get in, or you can pay 3 euros online to reserve an entry time.

The combo. ticket purchased at the Correr is a good way to go. You can eat a simple salad/sandwich meal in Correr cafe with a lovely (AC) window view of the square. The food is a bit pricey - but it's still one of the better food options on the square. Plus, use the bathrooms there! (clean and uncrowded). You can also access the Marianni Library. Then, walk across the square with your combo. ticket to Doge's palace. The Correr ticket puts you in the reserved ticket line which is either short or nonexistent. You can easily enter the Doge's Palace this way and avoid a long ticket line.
The Basilica as mentioned is free. However - there are several "side" features that charge separate fees to access. You just pay these fees one-by-one as you go to these separate features. (Example: bronze horse statues and balcony upstairs.)