Another Fences Suggestion

I love Fences.  Thank you.  My monitor though seems to have some uneven brightness/color problems - If I have a dark background and want my fences mostly transparent, they seem completely transparent at the top of my screen, but clearly visible at the bottom.  I realize this is my monitor's problem but it got me thinking:

It would be nice to have a setting so that each fence would have a different level of transparency on mouseover.  That way I could set it up so that the fences would be totally invisible until I mouse over one of them.  Or you could do the opposite, or have them different colors when moused-over etc...

Just my $0.02