[andreasvc]

Interlingua was constructed this way, at least its vocabulary. They made the mistake IMHO to make the grammar naturalistic, which made it very easy to read for people who already spoke a Romance language; writing, on the other hand, was made difficult by this.

You could perhaps use a typological database with grammatical features of the world's languages and somehow select an "optimal" combination from it, but that's a far cry from letting a computer determine the most efficient means of expressing information; we have no idea how to define information/meaning, so that it's still an impossible dream. I don't think the problem is that designing languages is hard per se, it's that people can't be bothered to agree on one and learn it.