Hearthpwn

Sadly, I don't think so as the problem is that the Deathrattle means it will have anti-synergy with Twilight's Call. You don't want to bring a Meat Wagon back or make copies of it. If it was a Battlecry rather than a Deathrattle it would've been great to get a Devilsaur Egg out earlier but as it is I don't think it's worth it.

Glad to hear you're having fun, less so that you went 9/16 with it. I did just do a big deck change update that should really help with aggro, feel free to try it out and let me know how it goes.

Fungalmancer would add another weak body for a high mana cost to the deck. It doesn't really do anything that Cobalt Scalebane over a turn won't do better. While the instant +2/+2 is nice, it doesn't give Taunt. Devilsaur Eggs already have plenty of ways to get attack (and any copies will be 1/1 and can already attack) and Skelemancers need Taunt more than they need stats. A Cobalt Scalebane is a card your opponent doesn't want to leave on the board and as a 5/5 it can trade quite well and also give a friendly minion +3 attack. If it gave Taunt I would consider it, but currently it feels like a less effective version of Defender of Argus.

You can try, but keep in mind that Oakheart could also summon Sunfury Protector, Defender of Argus, Glacial Shard, Mirage Caller or Shadow Ascendant as those all have two attack as well. Pulling a Shadow Ascendant is fine but the others are really bad because you'll miss out on the Battlecry. I think Oakheart can work well with a Druid deck though by pulling stuff like Crypt Lord and Grizzled Guardian.

Could you provide a bit more details? If with inconsistentcy you're referring to the fact that the Deathrattle minions might be at the bottom of the deck, there are some cards that help you draw into your deck or delay long enough to get one in your hand. Of course there's the chance that all of them are actually at the bottom but that can happen to any deck. If a Cubelock has both of his lackeys and skull at the bottom of his deck he'll struggle against his opponent as well. Also, keep in mind that this primarily a fun budget deck, not a big meta deck to get you to Legend.

If you have any suggestions to improve the consistency of the deck I'd love to hear them. I've considered additional Deathrattle minions like Cairne Bloodhoof or Twilight Summoner but both aren't cheap in dust and Twilight Summoner is rotating out soon. There's also the question what cards they would replace.

So far the main issue I've had is getting a less than ideal starting hand as the deck doesn't have *that* much 1/2 mana minions. Obviously starting with a Northshire, Shadow Ascendant and an Egg is perfect but sometimes you just get a bad draw and I haven't really figured out a way yet to improve those odds.

One option (but then you go outside budget range) is to add Twilight Summoner and Cairne Bloodhoof and hope the next expansion brings a nice replacement for Twilight Summoner. It does add 2400 dust to the deck cost and I don't have any of those cards myself so I can't judge how they'd work in the deck. It's also a question of which cards they should be replacing.

I haven't really had that much issue with Silence actually. Usually I got a copy off before that. And I make sure to spread my buffs as much as possible. The main thing that I've been losing to is the opponent getting (and keeping) board control and not allowing the deck to get any traction with the Deathrattle minions and killing me too quickly or going lategame with powerful cards like Guldan or Frost Lich Jaina.

Currently at 15, from having not played Hearthstone in ages since Naxxramas.

I'd say Scalebane, Power Word: Shield or a Sunfury Protector if you're not too worried about getting Taunts on the board.
Whilst Scalebane is a nice 5/5 body to throw on the board, it only really forces your opponent's hand if you already have some stuff on the board for it to make scary and it still dies easily to any removal or board clear.

For Wild you definitely want Nerubian Egg. It adds two more Deathrattle minions that are great to bring back.

The two cards you mentioned are also great, though I'm not sure myself what you could take out.
You could opt to leave out a Power Word: Shield and a Sunfury Protector. You'll have a little bit less Taunt to give but only the Skelemancers really need it. The eggs you can break yourself once they get any attack.

Hmmm, interesting suggestion. It does have a decent statline to play by itself, the only real downside to it is that it doesn't give you a minion on board when it dies to discourage board clear. That said, getting a dragon can be very good to play. The deck does benefit from having big minions that can then be protected by the Deathrattle minions from board clear. I might give it a try, thanks for the idea!