The phrase "added vastly" is not correct and does not sound natural in written English.
It could be used in a context where you want to describe a significant increase or enhancement, but the phrasing is awkward.
Example: "The new features added vastly to the overall user experience."
Alternatives: "greatly increased" or "significantly enhanced".
The mighty Gore Vidal has added vastly to the gaiety of nations with his latest memoir.
He added vastly to the vocabulary of the cinema and pioneered a personal style of filmmaking now integral to its practice.
Nikolay Mikhaylovich Przhevalsky, (born March 31 [April 6, New Style], 1839, Smolensk, Russia died October 20 [November 1], 1888, Karakol, Russian Empire [now in Kyrgyzstan]), Russian traveler, who, by the extent of his explorations, route surveys, and plant and animal collections, added vastly to geographic knowledge of east-central Asia.
In other words, scientists decided the universe's missing mass must be made up of undetectable particles which hurtle through space in colossal numbers and form invisible halos round galaxies, adding vastly to their masses.
And at a time when the country is sunk in $14.3 trillion worth of debt, it's adding vastly to deficit, too.
The payoff for building such a digital collection, he added, is vastly improved availability of a huge store of knowledge and information for teaching, learning and research.
And Diamond, she added, has vastly improved her learning skills this year, especially in reading, which she regards as her favorite subject "after recess".
On the other hand, if the code evolves by sequential addition, then there is a major selective advantage every time a new amino acid is added because vastly more proteins can be made with an alphabet of n+1 amino acids than with an alphabet of n.
Implant makers, who have realized vastly added sales from the Medicare ruling, supported the registry for one year then cut back financing.
What a waste of the licence fee payers money added to the vastly inflated sum that BBC pays for Wimbledon (no-one will watch it if it is on another channel so therefore they should down the price, not up).
When there is balance at the board table the results include a longer time horizon and more risk awareness with 21st Century management styles of collaboration, partnerships, teamwork and relationship-building are added to the vastly over-rated "decisiveness dynamic".
