Rolle is a huge liability deep. He was always letting guys run free past him, taking horrible angles, etc.. KP, Hill, Stevie are all consistently better in that regard. rewatch the games. The Giants did not trust Rolle deep at all. Why do you think they had him down near the LOS so often?
Now if you wanna debate who the better tacklers are then okay.
Take a look at the stats, Stevie Brown was better than Rolle in every category, except tackles.. which is expected because he didn't start until KP was injured. Rolle is terrible in pass coverage, which is a double negative because we have corners that can't cover for ****.
I wouldn't go far as to say Will Hill is better than Rolle, but from what I've seen.. I think he has the potential to be a great safety.