The phrase "a powerful addition" is correct and usable in written English.
You can use it when describing something that significantly enhances or improves a situation, project, or group.
Example: "The new software proved to be a powerful addition to our existing tools, streamlining our workflow and increasing productivity."
Alternatives: "a significant enhancement" or "a strong contribution."
The "Holding On" video, already a tearjerker, is a powerful addition to those contributions.
But they have retained three of last season's stars in Chris Martin, Craig Bryson and Will Hughes, while Cyrus Christie is a powerful addition at right-back.
I believe the digital medium is a powerful addition to the ways in which our students can interact with one another in an educational context.
Unreliable narrators take the reins of much fine fiction and Ruth is a powerful addition, drawing us into her intimate story, even as we lurch between doubt and certainty about her sanity.
Peter J. Grant, an analyst with the research firm Gartner Dataquest, called digital color printing very attractive to corporations, and he praised Indigo's technology as a powerful addition to Hewlett-Packard.
The result is a powerful addition to the city, an unsettling presence that is at once seductive and forbidding, an appropriately challenging container for the work that lies within.
Combined with the new Split View interface, Notes is shaping up to be a massively powerful addition to OS X as a convenience feature, and could easily become one of my most-used apps on the platform.
This organ seems a splendid and powerful addition to St . Ignatius Loyola
– June 14 , 2010– AT&T* and HTC Corporation ("HTC") today announced that HTC Aria™, a rich and powerful addition to AT&T's Android smartphone portfolio, will be available exclusively at AT&T beginning June 20.
Quick Version: Whether you're new to the Call of Duty series of first-person shooters or you've played some or all of the past versions, you'll likely find World at War to be a compelling and powerful addition to your library of games.
The applicability of MSCs to the treatment and/or prevention of bladder dysfunction by BOO would provide a new, potentially powerful addition to the limited armamentarium of existing therapies.
