3D Walk Path

I was given the task to animate a walk path in 3D. It isn't a walk cycle, as the object is moving from one spot to another, and not on the spot or in a loop. For this task I used the rig 'Monty' so I could concentrate on the movement, and because Monty is a very simple character to work with.

My first attempt at making Monty walk had mixed success. I managed to make him move forwards and his steps were quite consistent, however near the end he seems to move slower and his feet start to slide. The problem was I moved the foot on the floor when moving him forwards, so he appeared to slide instead of stepping forward.

I had more success in my second attempt. He does still appear to slide a little near the end, but not as much as the first attempt. I also changed the camera angle so it looks like Monty is walking towards to camera/audience.

I would really like to try this task again, if I get the time, so I can avoid the sliding feet and make the walk more consistent.