I play JS almost exclusively.
While your definition of 'content' might vary, most of the JS wrenches are unquestionably bad.
1) Lower selling prices. You cannot build or recruit as fast, tolerance for errors in build orders is minor.
2) Bad events start earlier and are more of them. Is that 'content'?
3) Enemy progression is accelerated. That means that stuff others have to deal one year in, mandatorily start in six months on JS. There are multiple readiness checks that other difficulties give you a fair time to prepare are rammed through on an accelerated timetable on JS. Expect to deal with checks in month 2 instead of month 8+, month 7 instead of month 12+, month 12 instead of month 24, and month 18 instead of month 30.
3) Dogfights are more lethal, enemies fire faster. Is this extra 'content'?
4) on battlescape, enemies have significantly higher stats, able to fire more accurately, move faster and react more.
5) the only mixed blessing: there are more enemies. The good part: more loot. Bad part: more enemies.
Note that JS is *explicitly* designed to be anti-fair, and Dio often goes out of his way to make JS unfair, or eliminate cheesy tactics.