Solarian is garbage. 7 mana to get a 6/6 that you can only attack with after two turns is a really bad rate. If you're playing 3+ colors, you have way better cards to fill your deck with. And once again, this thing doesn't have trample or evasion, so it can just be chumped. A 24/24 after 4 turns of investment isn't a monster, it's just.. Bad.
Jangling Automaton is.. Yeah pretty bad. If you're in a position where you need to defend your board... This thing is going to get blocked to death. You get one trigger out of it, and there's better ways to give pseudo vigilance. If you're in an untap-value strategy, there's way better cards out there. I just re-read it, and it's even worse. It's defending player. Meaning you don't get to untap ANYTHING, just your opponent. This only works in Jon Irenicus decks, lmao.
Table of the Guilds is garbage. If you're in lifegain, you have better options. If you're in anything else, why do you care about lifegain? I could see it being a cute pick in a budget "multicolor matters" deck, but in anything else it's just a waste of a slot.
Howling Golem only really works in decks that care about opponents drawing (Xyris, Nekusar) and those decks (you guessed it) have better options. Politicking to victory doesn't work if you give everyone resources, it's far more effective to give one or two opponents resource. Protecting yourself by boosting everyone else isn't a viable strategy, because once they're done with the other two they just have a stronger board than you and you're an afterthought. There are exceptions (like Vazi decks), but those don't want this thing.
Golem-skin Gauntlets is just a (really) bad Nettlecyst. Let's say you do you have 3 equipment attached to your Voltron creature.. Would you rather give it +3/+0 or attached another meaningful piece of equipment to it that probably gives more than that. 3 mana is quite a lot, especially since equipment decks are already strapped for mana.