Spring and summer flowering bulb suggestions please

I've got four smallish troughs that are sitting idle, so I thought I'd plant them up so I have a nice show of flowers next year.

I'd like some colour from early spring through to the end of summer.

I am toying with two options :

1) Spring flowering bulbs, followed by flowers grown from seed
2) Spring and summer flowering bulbs side by side.

I am looking for some suggestions.

Spring
I don't want any daffs or crocuses because I have those in the front garden. I do like snowdrops but what else can I plant which is fairly small?

Summer
Again, I don't want anything that grows too big because the containers aren't that big, so am open to suggestions for seeds or bulbs which would flower through the summer.

I love fragrance so if any of them were nice and smelly that would be an added bonus!

Thanks in advance :o