I've only been to Seattle once, in 1996, when West Seattle was just starting to get trendy according to my host. I loved it then, with all the water.

And with the closer commute and the ferry--it's a no brainer in my book.

Of course, I've never been to Renton.

I live quite comfortably in 900SF, so both options seem quite big to me.

Wherever you end up, I hope you enjoy it!