The phrase "a much larger issue" is correct and usable in written English.
You can use it when discussing a problem or topic that is more significant or complex than what has been previously mentioned.
Example: "While the budget cuts are concerning, they are just a symptom of a much larger issue affecting our entire organization."
Alternatives: "a far more significant problem" or "a considerably broader concern".
This is a microcosm of a much larger issue".
Coleridge said while Labor's credibility on asylum seekers was damaged, "there is a much larger issue I think of moral failure on both sides of politics".
The truth is, Amazon's heavy control and aggressive dominance of the publishing world is a much larger issue than the Hachette dispute," said the novelist.
But, while the White House press corps gnaws at that bone, a much larger issue also needs to be addressed: What lies at the bottom of Trump's Putinophilia?
Michael Ableman, a farmer and one of the event's organizers, said the concerns were part of a much larger issue, a "national emergency," in his words.
This is a much larger issue as these teachers might induce misconceptions in NOS to the science students under their care at the receiving end, either direct or indirectly.
"But this takes place at the heart of a much larger issue about the airline industry and how they treat people and the lack of respect they give to disabled American citizens, who they charge full price".
The whole point of that article was to show that it was a much larger issue, that women hadn't been permitted into the academies to learn how to make art, they were treated servilely, their work was criticized very dismissively.
Still others considered the Bush decision only a short-term response to a much larger issue--namely, the absence of any comprehensive federal law regulating the parameters of medical experimentation on children or adults, whether that research is publicly funded or not.
Dropbox and Tumblr also reported outages, pointing to a potential much larger issue across the web.
But if what you are truly after is transparency, then it seems a much, much larger issue is that of changing managers.
