Sorry - hadn't spotted this thread before.
In terms of the sentencing guidelines, this falls into category 1A. There are several mitigating factors present (remorse, previous good character, first offence, steps taken to address behaviour) and there do not appear to be any aggravating factors. He pleaded guilty at the earliest opportunity, which results in a one-third reduction in sentence. A 6-month suspended sentence is therefore what I would expect. Whilst it could be referred for review as an unduly lenient sentence, I would expect any such challenge to fail. This appears to be a perfectly normal sentence for the crime reported.