...I'd be really happy of stereotype updates could cascade from class to instances though!
I agree... that is important. Actually, I'm finding that support for profiles and stereotypes is rather thin in EA.
Yes, elements can be created and stereotypes assigned, and stereotype labels or pictures shown in diagrams or the project browser. However, stereotypes don't show up at all in selection lists, link lists, Matrix displays, and reports, etc. One stereotype is confusingly implemented - the objectflow, as some "check-box-indicated" adjustment to stateflow, but not as a unique base type or stereotype (for business modeling).
Some base types are confusing too. The base type "entity" supports aggregation but not generalization, while the similarly-used "actor" type supports both. Little seems consistent about stereotype and base type implementation. These things seem built into the EA code and are not customizable through table entries. Seems like a serious limitation for business modelers.