Homepage and Category page keywords

Which keywords to target on a homepage and category page

[Evian]

After receivig such good advise from my previous post, I'm hoping you on how to optimise my pages by keywords.

My previous thread:
[webmasterworld.com...]

History of my company:
My domain is my brand name as well as my product name, which together make my company name.
For example: www.abc-widgets.com where 'abc' is my brand, 'widgets' is my product and ABC Widgets is my registered company name.

My URL structure will be:
www.abc-widgets.com/blue/

I have identified 5 key phrases which I want to target from Day 1:
blue widgets
sky widgets (has the same meaning as 'blue widgets' but 'sky' is a synonym of 'blue'
cheap blue widgets
blue widgets SA
blue widgets online

My site will have 5 pages from Day 1:
www.abc-widgets.com/
www.abc-widgets.com/blue/
www.abc-widgets.com/blue/types/
www.abc-widgets.com/blue/types/material
www.abc-widgets.com/blue/types/liquid/

And my product range will grow in the next 6 months to include 'red widgets' and 'green widgets'

My question is ... what keywords should I target on my homepage from Day 1 as the term 'widgets' alone is very competitive and has a very broad meaning. 'blue widgets' has a more specific meaning. Although I don't want the homepage to only focus on 'blue widgets' as I will have to update the content soon to include info on red and green widgets.

Any guidance would be greatly appreciated. Please let me know if I need to add more clarity about my world of widgets!