Base level (3 amp points a level)
Change shape (drake) takes an attack
In drake shape,
Unarmed is choice
6 point armor, drake armor heals when revert to metahuman form.
Can glide.

Level two
Can fly
Dragonspeech
Dragon sorcery [used in both shapes]

Level three
Elemental attack (fire)

Level four
Natural weapon

Level five
+3 armor in drake shape

Advantages: if char has taken drake amp
heavy scales: +3 points of armor in drake shape

It's the order okay? Cost changes?

Why is the natural weapon level four?
That should come with level 1. You gain claws and big ass teeth with the change after all.
Gliding should be level 2. You need to learn how to use those wings after all.
And Dragon-Speech should be here still.
Level 3 elemental attack of choice. Also sorcery, because the elemental attack is basically magic anyway.
Level 4 flight and 3 more Points of armor. You have grown some more, you are tougher, your wings are bigger and you know how to use them.

Forget about Level 5.

Something like this?

Base level (3 amp points a level)
Change shape (drake) takes an attack
In drake shape,
Lose armor, weapons and equipment as they are melded into you. They return when you revert back to metahuman form.
Natural Weapons.
6 point armor, drake armor heals when revert to metahuman form.

Level two
You can glide
Dragon speech

Level three
Elemental attack (choose one)
Dragon sorcery

Level four
You can fly
+3 armor in drake shape

Advantages: if char has taken drake amp
<one for each type of dragon>

Heavy Scales: +3 points drake armor.

Underwater adaption: you can swim, breath underwater, you lose the glide and fly abilities.

Tail stinger:

???????:

cut that out.
you change, you lose all not drake form adapted gear. weapons, armor, everything.

That's how it works in 5th ed.

That's how it worked since time immemorial . .

Oops I miss read your post, not drake adapted.