Latejami was created to be a neutral interlingua used for machine translation, but is an interesting language in its own right. Created by Rick Morneau, it is a deep study of semantics. It also has a comprehensive derivation system where words are created by combining extremely broad, but short stems. E.g. -cap is any synthetic substance from metal to cloth to manufactured chemicals.
You can read more about it on its very old website.
Just read the intro of the reference doc, definitely gonna come back later and check it out in more detail
I’ve been reading more and this is fascinating. I kinda wanna take the underlying ideas and mangle them into a bit of a different form that fits my aesthetic wishes more… Very cool!
One thing I’m not quite happy with at first read is giving verbs a default argument structure for an unmarked root-only version.
On the positive side you save one syllable (which could potentially be recovered with a shorter root?), but on the negative, it both seems to invite importing assumptions from English, and also means there’s added information to memorize for each verb.
So I think I’d prefer always marking the verb.
I've gotten to the section on nouns and.... what? 
I did not expect this!