I think that the choice, realistically, for the future global language lies between English and Esperanto, rather than an untried project. As a native English speaker I would prefer Esperanto.
It's unfortunate, however, that only a few people know that Esperanto has become a living language.
After a short period of 121 years Esperanto is now in the top 100 languages, out of 6,800 worldwide, according to the CIA factbook.
It is the 17th most used language in Wikipedia, and a language of choice by Google,Skype, Firefox and Facebook. Native Esperanto speakers,(people who have used the language from birth), include George Soros, World Chess Champion Susan Polgar, Ulrich Brandenberg the new German Ambassador to NATO and Nobel Laureate Daniel Bovet.
Your readers may be interested in the following video at
YouTube - The language challenge -- facing up to reality Professor Piron was a translator with the United Nations in Geneva.
A glimpse of Esperanto can be seen at
lernu!: Main Page 