Id say Senior as he dealt with a better quality of player. The likes of Newlove, Renouf, Gleeson, Lyon and Hape.

Whereas now you have Watkins running round the likes of Gelling, Percival and the new world 'hide and seek champion' Shenton.

Different types of player, Senior all power with some pace, Watkins the more technically gifted & skillful.
Both great to watch in their different ways.

Senior for me by a great distance. He didn’t need to be spoonfed “good ball”. He made himself part of the action. He also brought every winger who played outside of him up a few levels

It took him a while to develop any kind of skill in setting up his winger. He was very much a biff and barge merchant early on. Also, whilst he didn't need to be 'spoonfed' he clearly enjoyed the physical side of the game, getting the ball at times when he was clearly going to get hit hard. As a result he was a far easier target than Watkins, who needs to get the ball in space. Its horses for courses. Someone mentioned Steve Renouf - you could never give him the kind of crash ball Senior got.

Anyway, there's no doubt if you were picking a team of the era, Watkins and Senior would be the centres.

True, but he did develop that skill. His running angles were also better in that they created space for his wingers.