Please allow more options in the DataSet OQL editor. Now very simple queries that require string parameters or date parameters are not even possible while it's perfectly possible in OQL.
For example: create a query that filters all invoices where createdDate > $dateParam is very complicated. You would have to create a long attribute that mirrors the createdDate and the use a long parameter in the DataSet OQL editor to filter on the mirror attribute.
The fix would be really simple, just make date fields in Mendix allow Long parameters (this now gives incomaptible DateTime vs Long error). Because in this query: createdDate > $dateParam my dateParam could be a long and it would work, since I could then pass the EPOCH long value of the DateTime attribute.
In addition it would be nice if we could do more with DataSets in Microflows (natively). For example, execute a DataSet query from a microflow (with parameters) and map the reponse to a result object based on the SELECT aliasses. This is already possible with a simple Java action, but it would be ideal if this would get native support.