I think this is the version I'm most satisfied with thus far. I lengthened the roll of the ball and tweaked the curves so that the speed was relatively consistent when coming out of the last bounce, and had it slow to a stop. The rotation was a little tricky to get right, and I'm still not sure it looks correct. I opted to have it roll for about one frame after it came to a stop, just very slightly, in the hopes that it would be a little more realistic. In reality the ball wouldn't stop moving at the exact point it stopped rotating... I think?
However, looking at the closeup shot, you can see a huge problem - it goes off-screen! It shouldn't be too difficult to fix (hopefully) - I should be able to use the fcurve editor. If I select all the x position keyframes and just drag them up/down to slightly alter the position, I should be able to re-frame it and bring it back into the centre.