It would be nice to have the the option to choose which feature layer or web map used in Crowdsouce Reporter application.
Also like to have the option to skip the login page of the application.
There are already several ways you can configure Crowdsource Reporter to show specific maps/layers. Crowdsource Reporter will show all editable layers in all maps that have been shared with a group in AGOL/Portal, so choose what content you'd like displayed in the app by choosing which maps are shared with the group and by setting the editing properties of the layers in those maps.
As for turning off the splash screen - that is under consideration for a release of Reporter later this year: Removing splash screen when PortalLogin is turned off · Issue #122 · Esri/crowdsource-reporter · GitHub
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