Ionic 3.0.0 Beta!

What seems to work for subcomponent modules:

@NgModule({
  declarations: [
    Subcomponent,
    OtherFriendsSubcomponentNeeds,
  ],
  imports: [
    CustomPipeModule,
    OtherModularizedSubSubComponentModule,
    IonicModule, // if we need <ion-*> components
    CommonModule, // if we need ngIf and friends
  ],
  exports: [
    Subcomponent,
  ]
})
export class SubcomponentModule {
}

Failure to explicitly export will cause template parse errors on things attempting to import SubcomponentModule.

<ion-nav> still hates me trying to use string class names.