Good question and I am not totally sure that this answer won't come across as vague and wooly... I suspect it comes down to personal preference but here goes....
Looking back over the years the players that have captured the imagination of the fans have been those that give 100%, have a very obvious edge and most importantly, those that make those around them much better players. We have been lucky enough to have some superbly talented individuals but the ones that stand out as being the "heart" of the Devils (Matulik, Michel, Voth, Adams stand out) are the ones that make me buy-in to the team.
I remember when Rick Brebant signed, he scored numerous goals, had numerous assists yet he was never taken to the heart. It was not enough that he was the best player on the team, instead it was assumed that he would be gone soon, the team was of lesser importance and sure enough... Galbraith's career (the three years at Nottingham aside) has seemed to follow a similar path. This may be unfair but feeling is always that here was a very talented individual rather than someone who made the team that much better.
If he signed I am sure that he would score a bag load of goals and would be a joy to watch but, would his influence be felt throughout the team? He failed (along with others) to motivate Nottingham to their first title since the year dot and was perceived to be one of the problems in terms of motivation. Given our lower budget, poor facilities and the extensive travel needed to get to away matches, I just can't see him fitting in long term.
See, told you it would be waffly...