"extensive arsenal" is correct and usable in written English.
You can use it in any writing where you need to express something comprehensive or vast. For example, "During the war, the country had a vast and extensive arsenal of weapons and ammunition."
Israel already uses an extensive arsenal of military, legal, social, cultural and economic tools to suppress Palestinian nonviolent resistance.
The most flawless of set-shot goal-kicking techniques was wedded to an extensive arsenal of more subtle talents.
They also elaborated an extensive arsenal of techniques and laboratory procedures for revealing the ubiquity, diversity, and abilities of microbes.
Her skin regimen still takes an inordinate amount of time; we rely on an extensive arsenal of potions and specialist clothing to keep her comfortable.
Backed by AOL's owner, Time Warner, the site is quickly amassing an extensive arsenal of shows and movies as it signs up more studios and television networks.
But in the trunks of vehicles outside, they found an extensive arsenal of mortars, fragmentation grenades, rocket launchers, submachine guns, radio-controlled bomb detonators, stolen police flak jackets and black hoods liked those used by terrorist attackers.
There was little doubt that India, with its far more extensive nuclear arsenal, stood ready to retaliate in kind.
But their extensive private arsenal is also ready to be deployed to repel, or more likely slay, intruders to the family home.
The death of one of Mr Putin's most outspoken critics, which Kremlin officials say was not picked up by any of the cameras in their extensive security arsenal, has led to widespread criticism for the Russian president.
The theory underlying the triad was that spreading the assets comprising the country's extensive nuclear arsenal across various weapons platforms would make the force more likely to survive an attack by the Soviet Union and to be able to respond to a first strike successfully.
Geagea has also based his campaign on a promise he can hardly keep: to bring Hezbollah's extensive illicit arsenal under state control and end the Shia organization's military participation in Syria alongside the Assad regime.
