well in the Wiki its says Lord Vanaduke does not actually belong to any monster family, although his lore leads to the belief that he is undead. He does not, however, share the same resistances or weaknesses as common undead. so your bubble burst yet

Please not T1. Need more T3 bosses. Otherwise, +1.

I completely agree that we need another t1 boss, imo we should have 2 bosses per tier in the current content.

gun: Having that many different types of guns is kind of contrary to the game. 2 shot guns that are ele and shadow are already alchemers, and they have that same relative speed. The only thing that you would be doing is making a different type of alchemer effect. Maybe have it as a 1 shot, and extremely powerful, or balance it with 3 shots much like the polaris series. But bringing in a gun that already has a counterpart is just going to cause controversy.

sword: You basically described a spur but different skin. I am all for a 5* version of the spur, but making another flourish/barb relationship is a meh idea. A cutlass is actually a short range weapon. So for this, I would say make it have the speed of a flourish, but have a normal damage type and wider swing speed, similar to BarbTB, but normal/shadow (possibly)

bomb: good idea, its a shadow version of DarkBB (the knockdown is really kinda over powered tho). This will allow you to bomb without blast bombing jellies and constructs, making damage bombing viable.

if they were to introduce armor into the t1 content, then you would also have to add it into the snarbolax boss (wolver). Which I kind of agree with anyway.