Here's an am-tip on crosshair color. (Hate to call it a pro-tip, I'm hardly a pro )
In my company we work a lot with x-ref'd images, specifically USGS topo maps. What this means is we get a lot of mostly white images pasted on to our black backgrounds and crosshair visibility sometimes becomes a hassle. Previously I would turn off hardware acceleration, which I did not like to do but DID make the crosshair invert itself relative to whatever color it was over. Recently I started using this setting instead:
Options->Display Tab->'Colors...' button then in both '2D model space' and 'Sheet / layout' pick 'Crosshairs' and under the color drop down is a checkbox 'Tint for X, Y, Z'. This changes your crosshair to be colored as if you were in a UCS even in WCS. Only took me a minute to get used to since UCS still changes the crosshair lengths along the axes (axii? axises?). For a little bonus I also changed the crosshair color to 254 (which we rarely-to-never use as a solid hatch) so the pickbox itself is still very visible against black, and somewhat visible against white. Having both the red and green colors means I can still identify the crosshair no matter what color background I'm hovering over, and I get to leave hardware acceleration on.
Maybe this is something all the true pros are going to say "yeah duh" but I thought it was a neat trick and thought I'd share.