Here are just some draft on ultramarines logo for my next army, the 4th company of the Ultramarines.
The first one with the wings would probably goes well with the assault squad while the second one resembles the tyranid fighters, which probably goes with some sternguard vets with thier special ammo. The third one is somewhat taken from the 4th company banner, symbolises the Fist of Ideaus and the last one is a variant with a lightning claw, probably goes well with vanguards...
These would probably be applied to certain vehicles as indication of dedicated transports, squad banners and certainly on the shoulder pads.
Comments are welcomed! :D