I don't think the Kratos boss looks that special from what I've seen, but the Battletoads thing looks cool, and I am somewhat jealous of XB1 owners of the game as a result.
And yeah, that whole amiibo debacle is pretty dumb IMO, and I hate how it locks behind something as basic as a co-op mode, and assuming the Shovel Knight amiibo is impossible to get at MSRP, it will be a disaster.
I still think Shovel Knight itself is a solid game, but I can definitely understand your reluctance.
I'd say pass for now.
"Just for comparison Uncharted 4 was 20x bigger than Splatoon 2. This shows the huge difference between Sony's first-party games and Nintendo's first-party games."