Dissapointing performance

Sorry to dissapoint you but today I made compression test to all cylinders and I drove car like 10 miles on medium load. After that ride I did compression test and I "readed" all plugs.

Compression test: 170,172,170,170,175,170,172,170. Very good results and even between cylinders.
Spark plug was coffee brown + very little black carbon on it. Like I said when car is driven higer load and longer time, then the plug shows its "real color".
I can upload pic of compression meter and plugs if you dont want to bellieve what I said.