Impression on Eclipse

Recently I gave eclipse a try and find the free IDE is quite good at functionalities, though they have not made them work together as smoothly as IDEA does. In fact, I think they have some innovations that IDEA can learn:

1. error highlight on package /project level. (I learnt IDEA is heading to this?)
2. instant highlight of the variable/parameter/class usage. (some body might find it annoying, but some times it is usefull, especially when you are studying other's code)
3. instant highlight for interface implementation members/overide members (I know we can see the icons on the gutter, but a customized color background is more comfortable to me)