Rivers - some suggestions please

We have been enjoying a number of evenings playing Medieval Spain of the 11th cent; Medieval Spanish, Andalusians and Fanatic Berbers. To add interest we used Forest topography for the northwest part of Spain, Hilly for the central area to Arable in the south.

Rivers are present in each topographical area however, for esthetic variation I decided to make some dry river beds.

In order to have the game remain simple I am thinking about using the same river crossing conditions to determine the speed which an element can negotiate the dry river bed.

However, I had also thought about classing this as rough ground, but some thought should be given to the river banks and troops under cover while in the river bed. Still, the village of dried honey colored stone and an olive grove are quite nice.

This is intended for friendly games so some suggestions would be welcomed.

cheers,