Welcome - I wanted to elaborate on my thoughts for this design ( #2 ) It is quite literally a "cornerstone", yet it also represents "Thinking outside of the box"....It might even be bundled with a tagline that mentions it in some way.
Its simplicity is memorable, like HRBlock's green block logo.
I like your thoughts - could we try lettering that stands up straight? My partners are trending towards lettering that is straight up as opposed to angled... I may be able to re-look at your logo with some different lettering.