After my 2.5" lift, my rear is 3/4" lower than the front, so I want to level it out. A little rake would not bother me either.
If I go 1/2", I'll still be off by 1/4", but its not that big of deal, but want to get as close as possible.
If I go 1", I'll get a little better than level with a 1/4" rake, which would be ideal of the two. Theorhetically, this would put me at 2.75" if the front coils indeed sits at exactly 2.5".
I just want to be sure whatever coil spacer I add, by going over the 2.5" mark, that it will not cause any additional suspension issues by sitting higher.