The W07 hybrid, with which Mercedes are aiming for a third consecutive title double and Lewis Hamilton a drivers' hat-trick, was unveiled on Sunday.
Technical chief Paddy Lowe said: "Our priority has been to identify the areas we were weakest and improve them.
"There were a lot of things that needed improving for 2016."
World champion Hamilton will drive the new car at the Circuit de Barcelona-Catalunya in Spain on Monday when pre-season testing gets under way.
Lowe pointed to the races Mercedes did not win last year - particularly Singapore, where they suffered a bizarrely uncompetitive weekend - as motivation to take a step forward with the car.
"While the car may look very similar to its predecessor from the outside, underneath there are quite a lot of mini-revolutions that make up an overall evolution for the new season," said Mercedes' executive director (technical).
Mercedes have dominated since F1 switched to turbo hybrid power-units in 2014 and Mercedes engine boss Andy Cowell said the company had made a "good step" in performance over the winter.
He said a decision by governing body the FIA to loosen the restrictions on engine development from last year to this had meant Mercedes "haven't had to restrict any of our development activity to a specific area".
He added: "Anything which could yield a decent efficiency improvement - and therefore a decent performance improvement - has been explored and we're now working to make sure our package is sufficiently durable in time for Melbourne."
Monday sees the first of two four-day pre-season tests ahead of the start of the new season in Australia on 20 March.
Hamilton will drive the car on Monday, with the world champion and team-mate Nico Rosberg alternating over the remaining days of the test.
The new Mercedes has already turned its first laps in a brief test at Silverstone on Friday, where Hamilton and Rosberg both drove the car.
Mercedes say their new Formula 1 car contains a number of "mini revolutions" in design as they seek to stay one step clear of the field.