I also like the color and layout of the index page. Maybe in the green block though, think about replacing the text "micro to small size companies", with a more upbeat sounding "independent professionals". That is probably more of how your target market thinks of themselves.
Maybe somewhere put a graphic of a caduceus, Lady Scales of Justice, and a CPA logo, to catch the eye of your target market.
Also on my big wide monitor the left and right margin are not anywhere near equal. With medical offices it might be wise to keep the old narrow format for the layout hardcoded in, but when it loads in a wide monitor it is not centered, and looks a little broken because of that. You might want to fix that up.
Overall I find the index page attractive, professional, and inviting to explore further into the sight. Good job with it.