As I keep saying in other threads, the base model was simply to reach a price point. The 13" cMBP is the best selling mac, which is why they kept it for another year.
The base 13" rMBP is clearly for someone who has the needs for a MBA, but wants to have the retina screen and look cool.
The cMBP is tolerable even though it's last years hardware because you can at least add 16GB of RAM and a 960GB M500 SSD in it even though it is a base model.