I like the design elements in #16 and #17. My concern is that they are hinting at Microsoft's Windows' logo. If the second staff of the H were within the green square, it might break that allusion.
As to color scheme, as I have posted elsewhere, I am fearful of lighter greens, which are suggestive of a legal practice which does environmental law. In the US, the color of money has been traditionally a darker green. Old accountant's eye shades and glass lampshades (circa 1923) were dark green with lighter highlights. St. Patrick's Day marketing is in between. Environmental marketing is light green.
I am look for the color of money or old accountant's eyeshades.
As to entries 18-20, those are very typical for law firms and unfortunately do not speak to me as being anything uniquely identifiable to a particular law firm.