The phrase "a more critical issue" is correct and usable in written English.
It can be used when discussing a topic that is of greater importance or urgency compared to others.
Example: "While there are several concerns to address, climate change remains a more critical issue that demands immediate action."
Alternatives: "a more pressing matter" or "a more significant concern".
"That's a more critical issue for the United States as a sovereign.
Nowadays that seems to be a more critical issue for the Landmarks Preservation Commission than what the rest of us will experience on the street.
Indeed, the senator complimented Mr. Bush and said he had learned from his rival that education was a more critical issue than he had initially realized.
For Arthur, a more critical issue for the future is what the Times Company should do about the medium that Bill Gates has said marks the beginning of the end of newspapers as we know them.
Given that a company's entire worth can be walked out the virtual door in a matter of minutes, it's hard to imagine a more critical issue for investors to tackle.
Under the saturation of a cell, the transmit power consumption becomes a more critical issue because power is a limited resource.
Compared to conventional policies, administration of the program is a much more critical issue.
But this week an even more critical issue comes to the fore.
Prescriber identification becomes an even more critical issue given the more recent emphasis on the importance of feedback to improve prescribing practice and minimise PEs.
Given the scarcity of available donor renal allografts, identifying which patients with pre-OLT renal dysfunction will regain renal function post-OLT becomes an even more critical issue.
Most of prior studies on this problem have the following two limitations: (i) they assumed that the virtual network demands are constants, which does not hold in real-world network since such demands may vary a lot over time; (ii) their primary goal was to achieve more revenues for the physical network, with no consideration of the energy cost, which has become a more and more critical issue.
