Here is one example I just randomly grabbed off the MOC site. Lots of very nice meanders. Also notice the alluvial fans.

The steepness of a slope will effect the way meanders form. They do not get very wide on steep slopes, were there water flows quickly. On shallow slopes, water flows slower, meets more resistance and thus, meanders more.

Some good articles on Meanders
Meanders

Meanders

In the Mars picture, the crater wall starts off steep and then the slope lessons until it flattens out on the crater floor. Notice the meanders are in the middle section. They would probably continue down to the crater floor and become wider, but I suspect the water evaporates and soaks into the grown before it can reach the crater floor.

How theCoriolis Forceplays a roll in Meanders.

I remember in one of my College Geology classes where the professor suggested the Coriolis Force is what gets a new straight stream to meander. This Coriolis Force gets the water flowing in a corkscrew path as is flows down steam. This cause more resistance on certain areas of the banl, and less resistance on other parts of the bank. The stronger resistance cuts into the side of the bank, where less residence allows the water to drop its load and develop bars.

Some Geologic Principles dealing with fluids

I have yet to find and oxbow channel on Mars. My take on this is that water does not flow on Mars long enough to create an oxbow lake. Oxbow lakes take time to produce.