I think they are fantastic personally. I see alot of elite infantry and knights in my meta and vs those sorts of troops Skinks and Saurus die the same. So for half the points i like to have skinks soaking up the hits.
The Kroxigors also work as great can openers vs knights and dealing with monsters, as a unique unit they can't be thunderstomped/stomped.
I run 30 skinks, 3 krox usually and its works out pretty well. Template attacks on those blocks though can decimate bodies with T2.
I haven't played with it much but lore of light I think would work wonders with skrox units. giving the skinks WS 10 and pha's protection will make the enemy need 6's to hit which will almost always end in combat going your way.