How many seeds do you really need?

I have seeds for many different vegetables and many different varieties of most of those vegetables. So I've been wondering how few do I/you really need? 
Let's start with essentials - the veg that you always grow and couldn't do without. For example - tomatoes - but which one?

Let's start with 10 (or less) essential veg, then we'll narrow it down to naming the variety. 
 My essential veg are :-
Tomatoes
Courgettes
Lettuce
Mangetout
Beans
Cucumber
Rocket
Kale

Oh this will be very interesting

Tomatoes
Courgette
Squash
Pumpkin
Chilli
Basil
Kale
Lettuce
Beans
Broccoli

My essentials:
Tomatoes
Cucumbers
Courgettes
Beans
Carrots
Broccoli
Sweetcorn
Peas/mangetout
Onions
Chard

Tomato: Gardener's Delight
Lettuce: Little Gem (mini cos)
Bean (pod): Montegusto (yellow climbing)
Bean (dry): Jacob's Cattle
Courgette: Rugosa Friulana (yellow, warty one with delicious nutty flavour)
Pumpkin: Uchiki Kuri (small orange squash)
Basil: Greek (small leaves)
Sweet Pepper: Jimmy Nardello (thin red pepper)
Chili: Basque (very fruity and mild)
Mangetout: Green Beauty (purple flowers, tasty and tender)

Here’s what I grow each year.

Tomatoes
Cucumber
Basil
Lettuce
Chard
Kale
Courgette
Carrots
Parsnips
French beans