There are hunderds of quests in which you, as an adventurer, investigate some mysterious and potentially dangerous relic and deal with it. It is staple quest design which appears a lot. That is quite regular basis.
Then you have a loot you get as player after defeating bosses in either raids and dungeons. That is yet again, regular basis for us, adventurers.
As you pointed out, there are also some raid mechanics which forces us to interact with some objects/artifacts, all while we are not "explorers". That pretty much shows you don't need any particular expertise to use such items.
For these reasons, basing a class around usage of items is very weak and not interesting design choice, because everybody does that all the time.
Back in Legion, you as adventurer did it every day. That is regular basis. The only reason why we do not use artifacts anymore is that we sacrificed their power to drain Sword of Sargeras.Which again is not on a "regular basis".
Well, one is just regular interrupt every class (except healing priests) have, the other is already existing consumable item created by a profession system and third one is using a mount. You have nothing unique here. New concept which would make players be excited about this class.That's a matter of opinion. While I wouldn't consider a whip an artifact, Ancient Weapon Oil is a potentially interesting ability, and the ability to ride a Devilsaur sounds cool. I'm also looking forward to seeing how Gatling Wand turns out.
Well, because you know, you don't neeed to be any particular class to use an item, as I explained to you above. Every adventurer does that, which is why your explorer class concept is extremely shallow and completely lack any depth and potential for growth and expansion beyond "I hit things with whip and nobody else does it".Again, I'm simply going off of the abilities of Artificer Xy'mox, and he's primarily pulling power from relics and artifacts. Brann and/or Reno does the exact same thing with Relic or Uldum and/or Gatling Wand respectively.
I can imagine that explorer concept could be, in a way, translated into a secondary profession, possibly in revamped Archaelogy.
It has some gimmicky visuals and mostly non-serious fluff, which would be fine for a non mandatory profession. That is fine.
Hunter hero spec could also work, potentially, but I would have to see how it is done. As you said, in comparison to other existing classes, such a flimsy concepts sounds more like an afterthought. It has no real "meat" to it, nothing others can't do.