Yes quite so, OL. The guidelines have become more prescriptive over the past five to ten years or so but, as somewhat of a contradiction, have become more fragmented and detailed.
A paedophile not taken to court is nothing to do with inconsistency in the sentencing guidelines, ummm. Whether a case is taken to court is a matter for the CPS who act under their two part test. Your description of the case with broken face bones is not much help without the rest of the details (which you possibly don't have) but if the charge was ABH, even a "Category 2" offence does not guarantee a custodial sentence. Similarly you have not given details of the respective parts that the "big black guy" (who got 2 years) and the "white guy" (who got community service) played in the same incident. Nor, of course did you provide details of their criminal history (a very important consideration). (Please don't bother to do so because such exercises are a waste of time).
If you study the sentencing guidelines (which I know you see as a waste of time but, rather tiresomely is the basis upon which all sentencing is undertaken) you will see that it is not as straightforward an exercise as you would like to believe.
Anyway, I'd rather not get involved in a slagging match. I've answered charlytizzy's question as best as I can.