Add Item but either to virtual List or an Order ID

Hello All;

trying to develop something in my head but before i start perhaps someone can lend me some advice.

E.G.

BUttons with Global Values are going to be users choice

When they Click / select the button, the item is added to their order, however,

When they click the second option, the amount is changed based on user(s) 1st selection,

Eg 2:

Choice A

Vanilla 8in Cake

Choice B

Chocolate Mousse Filling ( + $5) if 8in cake

Choice C

Style #ABC)

+ $7.50

If i use Customers Table --> Orders Table--> Line Items <---- Products Table --> * Think the attributes table would need to be here*

But i have heard so many bad issues with collecting data using the Entity Attribute Value.

Any Ideas as what i am trying to build is customized items 80% of the time or something like that.

-i