A single world language should be designed and promoted. Previous attempts have been too Eurocentric to take advantage of all useful grammatical features that are available.

Alternative option: English is already a de facto world language, and it is well suited to borrowing foreign terms when it needs to, but humanity should be ashamed that it conducts its main scientific, commercial and diplomatic operations in a language with such a defective writing system. Spelling reform (or a completely new, purely phonetic alphabet) is urgent. I would advocate adapting Hangul for that purpose.