Token scaling

[mPicart]

I want to make my own tokens and have been doing some reading on the boards. From what I understand, the tokens sold through FG are (so I will assume these are "standard"):
Small = 53x53, Medium = 70x70, Large = 140x140.

It took me a while to finally understand that the scale of the tokens has nothing to do with the grid scale. The scale the tokens are created in just determines the details they display and also determines load times for clients attaching to the GM's Host (correct me if I'm wrong). The grid, on the other hand, just scales the distances on your map; so, for example, 50 pixels, is 5 feet across. So the important thing is the scaling of your tokens to look correct on your selected grid size on the map (again, correct me if I'm misunderstanding this).

By the way, I noticed in one of the tutorials a 2x2 white dragon in one of the combat sequences, which I assume is a 140x140 token. How pratical would it be to make tokens to follow the sizes in the d20 rules below? Unless it was very young, that white dragon would 3x3 or even a 4x4 creature!

Size, Creature Example, Squares taken
Small, Goblin, 1
Medium, Human, 1
Large, Troll, 2×2
Huge, Death titan, 3×3
Gargantuan, Ancient dragon, 4×4+