Right now, don't promote any of them.
Silvestor - playing some pretty good football, but do we need another FB at the moment? Not worth the cost at this stage.
Cartledge - see above
Howat - not shown enough yet coming back from injury. Plenty of other better options for his position to justify the cost.
Collard - hasn't shown enough. Why elevate him when he can barely crack Coburg seniors?