"considerably expanded" is correct and usable in written English.
You can use it when referring to something that was enlarged or broadened significantly. For example: "The company's product range has been considerably expanded since its launch."
During this era France considerably expanded public investment in the economy, health care, and education.
The deal grants considerably expanded rights to ethnic Albanians to use their language and be represented politically.
Since then, the three museums — the Prado, the Thyssen-Bornemisza and the Reina Sofia — have been considerably expanded and overhauled.
But Mr. Wagoner said in an interview then that the yen was less important than it used to be because Japanese manufacturers have considerably expanded their production here.
Crowton, the 44-year-old former Chicago Bears offensive coordinator and Louisiana Tech head coach, has considerably expanded the Cougars' playbook.
The United States has been experiencing the biggest surge of immigrants since the late 19th and early 20th centuries, when European immigrants considerably expanded the population.
Under his leadership, China acquired a rapidly growing economy, rising standards of living, considerably expanded personal and cultural freedoms, and growing ties to the world economy.
The Passover liturgy is considerably expanded and includes the daily recitation of Psalms 113 118 (Hallel, "Praise"), public readings from the Torah, and an additional service (musaf).
The emphasis on heavy industry has considerably expanded two traditional industries petroleum and natural gas but engineering, light industry, and food production are also of growing importance.
The committee was provided for in the understanding that emerged at the European Union summit meeting in Nice in December, but the British considerably expanded its role in their paper.
Within five years, he had revamped the roster, polished its sound considerably, expanded its regular programming and added special series like Meet the Moderns, in which he presented an inclusive overview of contemporary composition.
