Not sure if you've seen them yet, but your SMB1 Thomas customs led me to make the cast of Bob the Builder like them (in the same size and palettes) last September.

IMO, he needs a bigger sheet so his crane could be split into individual sections and have more angles for the jib (up to 45°) like I made for Lofty. For contrast, the separated hook and its cables should be in a "box" with a brighter background to make them visible. For the middle and end sections, add an instruction to help users extend/retract them if they want to (e.g. by adding/removing a few pixels to each one). I'd also animate his stabilisers going down for when he uses the crane.

Thomas and Edward's numbers should be a lot taller and they need different faces and/or some of the rivets to look more like their Railway Stories designs.