In my days as a VB developer I found a feature of the combo control very useful, which perhaps could be considered for Gambas.
Each item in the list has a display value (text), and an integer index to describe its position in the list. This is the same as the Gambas combo control. However the VB control also has a "key" property which was very useful in applications where the display value had to be translated to an integer ID to be saved to a database.
In my Gambas applications I achieve the same result by declaring a dynamic integer array and updating it in parallel with the combo control. It would save a fair bit of coding to simply have a combo.current.key property.
Sadly I think the standard of my coding is now too rusty to do an efficient job of creating the control myself.