I've been having a complete blast with this deck. Only played for one day, rank 5 to 4, so can't give much data, but I'll give you an idea of why I like this deck so much, and why I prefer it to Dog's variant (he hit legend 22 with his so I can't claim mine is better, but I'll leave you to judge what you prefer).
This deck is designed as a control deck. Consequently, it has aoe, healing, anti-fatigue measures (that also erases bombs f.t. Archivist Elysiana), weapon removal (Waggle Pick, Wrenchcalibur, and a lesser amount of Spectral Cutlass are common and very nice to destroy) and insane value generation. The overload spells are generally great for control, and complement some minions for early game tempo that if left alone win you the game. They can also be played from behind to catch up pretty effectively. So just play the game for tempo in the beginning, keep their board clear in the midgame, and ouvalue in the late game. Same plan for any matchup.
Unbound Elemental, Menacing Nimbus, Walking Fountain, Thunderhead, and Electra Stormsurge are all elementals. This makes Earthen Might a great card here, because in addition to it just being a great tempo card, it also will offer value half the time. One in three games I find space to pair it with Zentimo, getting +4/+4 or +6/+6 on the board and generating up to three elementals (usually 1 or 2). Earthen Might on Walking Fountain also often clears two minions and heals for 12, if you find yourself in the late game and those two cards in hand. I've also often been able to Electra Stormsurge into Earthen Might for a 5 mana 7/7, put two random elementals in your hand.
I love this package. It just screams tempo, value, and potential highrolls.
Sludge Slurper is simply a great turn one play. Zap! is simply amazing tempo removal when you need it. Lightning Storm remains a great anti-aggro tool. Don't forget that Zap! and Lightning Storm are pretty good when paired with Electra Stormsurge, and Zap! is great with Zentimo. This package is just good as is.
What makes this package even better is the inclusion of Unbound Elemental and Thunderhead. Unbound Elemental, if dropped on turn three with a Zap! to deal with a minion or on turn four with a Sludge Slurper, becomes very difficult to remove. An overstatted minion + and high tempo overload effect is just good. They either have to expend resources to remove it as a high value target or they leave it up. And if they leave it up, it can snowball some more. And it's also just a solid three drop. Gotta smooth out that curve.
Thunderhead follows similar logic, but focuses more on tempo. It's a pretty good body that can be played on curve and demands removal, or played along with some overload cards to get some additional 2 damage. Very good for board control. Also, don't hesitate dropping an Earthen Might on either Unbound Elemental or Thunderhead. Makes them that much more threatening.
If you find that 6 overload cards aren't enough to justify the package, you could play around with Lightning Bolt. I personally find it enough, and late game, Hagatha the Witch can get you some more overload cards if you still have the package in hand or deck.
Also, Bloodmage Thalnos is good with most of the spells in this deck, and offeres draw.
Hagatha the Witch is amazing, as always. Swampqueen Hagatha can pack a lot of tempo, value, healing, etc, depending on your picks. Archivist Elysiana delays fatigue and gets rid of bombs. Barista Lynchen is a odd choice that I'm not sure will stay but I find it too much fun; it can copy lackey's, Electra Stormsurge, weapon destruction, Shudderwock, Swampqueen Hagatha and her horror, Menacing Nimbus, and Archivist Elysiana (I'm not saying that some of these are likely, but they are possible). Shudderwock nets you some elementals from Menacing Nimbus, can have a three damage aoe from Hagatha the Witch attached to it, can replay the spells from Drustvar Horror and create another one, can delay fatigue by yet another ten cards, can destroy another weapon, can create more lackey's, and can copy battlecry miniosn on the board from Barista Lynchen. It's just a whole lot of value potential. There's enough synergy that something will work.
There are a lot of weapons running about. Hunter, warrior, and rogue are doing well, and they all run weapons (sometimes hunter doesn't, but still). A Harrison Jones and Acidic Swamp Ooze does the job[/card].
Bomb warrior can kill easily when you near fatigue, just through the sheer volume of bombs. Hence Archivist Elysiana is both anti-fatigue and anti-bomb. Witch's Brew can also heal you out of bomb range. My only considering is adding a second copy, but I'm not sure how to fit it in yet, but Walking Fountain I think does the job as additional heal.
Token druid fills boards repeatedly. 4 aoes are there to help, and stuff like [card]thunderheard[/card[ can hopefully win you the board so that you can control the board through board control and not just through aoe. Tempo is important here.
Zentimo into Hex is really for those big hand mages and priests who can create a board very big minions in one turn. If you can't do that, a Hagatha's Scheme drawn early can do a great job, since their minions don't have deathrattle. I recomend mulligaing for them in those matchups.
Zilliax. Sustain plus tempo. Just too good. Not sure what to take out for it.
Lightning Bolt. More overload and good removal.
Rain of Toads. Is a very good stall card, and is another overload card.
Let me know if you have good ideas on which or what other cards should be in this deck, and what to take out for it.
Cheers and have fun! Might make a mulligan guide if this guide gets attention, but I doubt it will so I'll leave this for now.