Trials will have a bearing, predominantly on maybe two or three positions and bench make up IMO.   You are right with 
RTS definitely a lock in.  There is zero chance 
AW doesn't pick him for round 1.  I'm hoping it's at left wing and the signs are kind of pointing that way.  I think some combinations or the position some players line up in will be up in the air.  For example, 
CNK if fit, will be a lock in.  What position he plays may be still to be determined - fullback, center, wing ...
Like I say majority of the team 
AW will already know in his mind and the remaining few positions will be up for grabs.