A talented kid who over the off season has put on a lot of bulk but is also injured and is in a moon boot, should be right to go after Christmas. When he did play seniors in the WAFL he didn't look out of place and he improved his disposal efficiency. Being on the rookie list though i don't think he will get a look in unless there are injuries to a lot of our mids. If he has a strong year i can see him being upgraded for 2016.
Some notes on the other players you mentioned.
Karpany - He was suffering from mild OP leading up the season but slowly worked his way back to play 15 games though the seniors and reserves. Didn't have a major impact but he did show signs of talent when given a go but struggled as he didn't have that much of a fitness back coming into the season. This is the sort of player we need to fast track as he will be handy as that rotating mid/forward. From some reports he has come back in good nick and ready for a good crack. Has a ready made body just needs the fitness so i hope he gets there so we can see him play in the WCE squad later in the year.
Barrass - Season ruined by injury but was put away early to prepare himself for this year. Has put on quite a bit of bulk which he will need if he is to be a power KP defender. A project player so will take a few years before we see him line up in the WCE squad.
Main - Tall mid who hasn't played much seniors but did play well in the reserves. A project player who could be anything at the moment.
College - Forward turned Mid who has been unlucky with injury through out the year. Played some great footy in the WAFL and was given a few games in the AFL. Was used a sub though where he didn't really get to use his talents , needs to be playing from the start.
Powell - Have no idea really.
Mcinnes - Has been coming along nicely but i think he will find it hard to get a crack in the seniors unless there are injuries to Darling, Jk and Mcgovern. Has been playing down back to see if he can play that role down the track.