The web and gold are both KKG.
Many of those techniques have costs well below their stated power with insufficient drawbacks for such a reduction.
Rain of Spiders is a technique used by the summon, so it can be included here, but will need to be posted on the summon page when it's made and the cost will come entirely from the summon.
War Bow needs a designated rank and power. It can't hit X-Tier.
Spider retract needs an upkeep as a transformation technique or a better explanation for how four arms get sucked into a body without enough space to contain them.
Scientifically, spiders produce non-adhesive threads to walk on or make minimal contact with the web to avoid sticking. What spider tag proposes would need to be done through chakra. That means upkeep.
Golden Buddha popping out at S Speed is too powerful, especially using the ijutsu route. With its range, it sounds like you can shoot the thing at people. That true?
Sticky Mimicry is a no go from me. Just use assimilate all creation.