If you want to always cascade into Phalanx/Weaver, you need to cut the other creatures at 6cmc and below (Kohlagan, Dragonspeaker Shaman, etc).
It's not impossible, but you need a lot of ramp and/or a lot of removal spells to stay alive on turns 1-to-6.
Search scryfall for cards like Fang Dragon or Spitebellows that have high mana cost but can stil be used in the early game.
Cuttting that stuff makes it harder to hit the 21 7 drops to actually hit the 1 of the 2 6 drops. The 3,4, and 5 drop
dragons are part of the tribe. No need to sacrifice any of the early stuff and they are just synergistic playables. With 17 different ways to produce some sort of mana accelerant which is from treasures/lands/and mana reducers. It really isn't to hard to get something out especially any dragon early. With 12 different removal spells which includes a few
dragons. Such as per example
Deathbringer Regent,
Siege Dragon,
Spawn of Thraxes and
Thunder Dragon. Recurring spot removal of
Spit Flame and the deck allready runs
Fang Dragon for it's versitility. It's just a $65.00 budget deck excluding the basic lands. Agree it isn't fully optimal but it will work. Anybody can take this shell if they so
wish and add whatever they want into the deck to make it as optimal as they want.