No more than the bard now having four subclass levels instead three. Actually, far less - its super easy to just say "level 1 feature is now level 3. level 6 stays the same." Etc.
EB is probably a class feature, sure.
Here's the thing with the pact forms. At least this is my guess based on Xanathar and Tasha invocations. Sword/book/chain/talisman are all things you make a pact with as well. Like, the Hexblade pact was made with a sapient weapon - now, all blade pacts are similar. Talismans are designed to work with Genie pact and give you, well, basically genie lamps, but could also be any other kind of Sealed Evil in a Can that you contact the spirit within. Book invocations in tasha had a whole "sign your name in my book of contracts" vibe going for it. And, naturally, chain is all about getting your spells through a familiar.
I'd like to see things keep going that way for the warlock pact types. It really helps give a bit more flavor to the style of pact you make. Very flavorful.