This is the newest iteration of the dragon deck I've been playing for the last 10 years. I'm trying to build it as optimized as possible without it becoming a cEDH deck. I'd estimate it at a 8-8.5 on the standard EDH power scale. It is capable of winning on turn 4 through a combo-kill, but it is much more likely to win turn 7-10.
You know why Sol Ring is in the deck, so I won't touch on every card, but here's a brief breakdown.
Combo-kills - I have recently considered the infamous 1-card-combo of Molten-Skittles as a way to make this deck a little more competitive, but I think I'm going to hold off for now. I am currently running a couple 2-card-combos in the form of Savage Ventmaw+Aggravated Assault and Niv-Mizzet, the Firemind+Ophidian Eye. I usually play this deck "fairly" and rarely go for a combo-kill, but these cards are good enough on their own that I don't mind them taking up a slot.
Lands - I am running all 10 fetchlands and OG duals for silky smooth color fixing. The rest are either 5-color or utility. However I do run at least a handful of basics in every deck to fight through Blood Moon-type effects.
Ramp - First of all, I understand Shard Convergence isn't ramp. It's in here for color fixing and to guarantee that I hit my land drops. Chromatic Lantern is also more for fixing than ramp. I obviously prefer ramp at 2 mana than 3, but beggars who want every color can't be choosers, hence Dragon's Hoard and Expedition Map. Birds of Paradise and Farseek are great. And I suppose I'll also include Mirari's Wake, Fist of Suns, and Belbe's Portal here as well. I have had excellent results with each. I haven't gotten to play with Kaalia of the Vast much, but she's done a good job of cheating dragons out. I guess that's kinda like ramp...
Draw - The deck definitely needs work in this category. Rhystic Study is on the list but suggestions for other efficient draw would be appreciated. I'll give Dragon's Hoard another shout-out as it draws me a nice handful of cards every game I use it. Ophidian Eye is more for the Mizzet combo wincon, but does fine when used fairly. I wouldn't consider The Ur-Dragon as reliable card draw - more of a nice Scion target that happens to draw cards. Sarkhan Unbroken can do work if he isn't immediately targeted out of the game. I consider tutors more of a better cantrip than a draw spell, although Demonic Tutor will forever be a part of this deck. Dragonstorm however is one bad game away from getting the boot. I still have yet to get even 1 storm copy, so I'm usually just paying more for a single dragon.
Kill Spells - Most of my removal is sorcery-speed, but cheap and flexible - which is a fair tradeoff imo. Hull Breach is an unsung hero of EDH as a 2-for-1 that can dismantle most engines and prevent a player from running away with the game. Vindicate being able to hit lands is handy, as Strip Mine is my only other way of dealing with Maze of Ith. Darksteel Mutation is incredible at locking down a player who relies on their commander to win. And Treachery is one of the best creature removal spells in EDH. Utter End might eventually get switched with Anguished Unmaking, although it's not my top priority.
Board Wipes - Living Death, Crux of Fate, Kindred Dominance, and Deathbringer Regent usually leave me at an advantage. Nevinyrral's Disk and Ugin, the Spirit Dragon are colorless and also hit noncreatures. And I can get Ugin back with Haven of the Spirit Dragon. Obvious rift is obvious.
Defensive Scion Targets - Scion copies these dragons in response to a targeted kill spell or board wipe. Sometimes, simply explaining that "bad things could happen if you target the Scion" is enough to get your opponent to point the spell at something else. The Kamigawa spirit dragons are great deterrents, as are Destructor Dragon and Quicksilver Dragon. Silumgar, the Drifting Death is great as a quick instance of hexproof.
Offensive Scion Targets - Scion copies these dragons for combat purposes. Nicol Bolas is probably the scariest dragon you can send at a player and he can be copied as a combat trick. Balefire Dragon might be the second best combat trick in the deck, wiping defending player's board in response to no blocks. Tyrant's Familiar is a bad combat trick, but it's ability to deal 7 to an opponent's creature is a great way to make friends. Atarka, World Render, Utvara Hellkite, and The Ur-Dragon all have great "on-attack" triggers that get better the more dragons you have. Hellkite Tyrant is more of a combat trick to steal mana rocks than it is a wincon.
Other Value - The other random dragons and reanimation spells should be obvious. Bladewing the Risen is probably the prime example. But there are a few powerhouses in this deck that I wanted to mention. First of all, Spirit of Resistance is the MVP of the deck. That card has won me so many games. Asceticism is easily the next best card, as playing dragons and revised duals apparently paints a target on your back. Third place goes to Teferi's Protection which has saved me many, many times. And with my deck being almost entirely sorcery-speed, Vedalken Orrery gets an honorable mention.
So that's my baby. You can see I sprung for a bit of luxury, but this deck becomes much more affordable if you go for the cheapest non-foil version of every card. If you swap the OG duals for shocklands, it's damn near budget. There are still a few changes I'm considering, but it's getting close to it's final form. If you have any suggestions or questions on the performance of individual cards, drop em in the comments. Thanks for checking it out!