McManus, hasnt performed to standard in a few seasons, once its gone i dont think it will come back, with Likiliki his young and talented, and could do a better job.
Edwards, has a great defending ability and can get good hard metres done, from the 4 games of FG he played last season, he stood out and performed better some off the other props, and he seems to have a good attitude towards games. so i would choose him over tui.
Paterson, struggled last season to perform, once he has performed then yes he should take mikas place.
Hilder, is an impact player, !