[Phlogiston]

Actually, when grafting, especially veneers, jagged, uneven junctions are your friend. Strait lines, like they did at the factory (repairs) are very noticeable. On trim that has dark tonner on it, almost any method will look OK. Filling broken edges with wood putty will just make them weak and prone to damage. The grafts are strong. I have never had to deal with one a second time. If the trim is going to have little or no color added then a pile of old cabinet parts comes in handy. Wet the closest match (lightly) and the original trim to see how good a color match you will have with finish on it. Fresh sanded wood may be an entirely different shade than you thought.

Good luck