Rate? Based on what usage or budget criteria?
What's it for? What are you gonna do? how much of what ?
Can you afford to upgade various subsystems ?
What sorts of insight, suggestions, answers are you looking for?
Why is it that you decided to build? Why now? can you wait?
Anyway, looks fine and well balanced, at first glance but we really would need to know, what you are planning to do with it and what your plans are in the coming 3-5 years (the life of the system)?
Would help ... there *is* a form at the top of the forum page, that gives some pointers on "how to ask"
= best of luck =