Sorting - Allow the user to choose which layer field to use for sorting

The Feature Iterator is a really great tool for looping through large vector layers collection. Being able to Pan+Zoom to next feature is already very useful (thanks for that recent addition), as well as filtering over a categorical field specific value.

A welcome addition would be to let the user choose a field other than feature-id to Sort the features - say by any numeric field, or even Date and datetimes. No real need for sorting positive/negative since there are already the next/previous buttons.

Another useful feature would be to let the user filter via standard qgis filters, via expressions - so the user could do filters other than selecting a single category for a categorical field. But this second feature is probably for more specific use-cases.