Hi Antonio,
congratulations for the board.
If you're satisfied with it I'm definitely not. The accuracy of it is just standard 0.025mm. (For comparison have a look at your PC's mainboard. There the accuracy has to be 0.0025mm)
You talked about multi-layer boards which isn't the case here.
Finally a hint to think about: Traces have to undergo stress, caused by thermal problems and resulting in mechanical problems. A trace layed at a right angle will have put unnecessary stress at abnormal thermal conditions, like ambient air temperature in the vicinity of high power switching devices which might produce temperatures of more than 100degC. Dividing the traces into sections of 45degrees will divide the mechanical stress by 1/2 thus ensuring better mechanical stability and hence better electric behavior and life time of the device.
Boncuk