Prefect Ron? There's worse.

[Joe Goodwin]

No: HPFGUIDX 151223

Magpie:
Draco seems easily as logically picked as Ron--he's a more obvious 
choice, actually, imo.  He is a leader in Slytherin house.
   
  Joe: 
Is he a leader in Slytherin? Aside from Crabbe, Goyle and Parkinson 
do we ever see other housemates following his lead? I can only think 
of two times, the "Potter stinks" badges and the "Weasley is our 
King" episode.
    
  Magpie: 
He's a perfectly competent student as far as I can see. <snip>
Harry would let us know if Draco was struggling academically, and 
he never does.  <snip>

As I said with Ron, I think the idea is more taking people who have 
certain qualifications and trying to channel them in a productive 
way.  Nor is it a disaster in Slytherin.  Draco is awful under 
Umbridge in the IS, which is a completely different system, but 
despite all of Hermione's warnings we don't see him abusing his 
powers when he's just a Prefect.  Hermione herself can also benefit 
from being Prefect--she's not so adept at the job she's ready to 
teach others yet as others have suggested, imo.  She just has her 
own set of issues and is quick to criticize what other Prefects are 
doing. 
   
  Joe: 
I think this hits the nail on the head. Malfoy is a fine Slytherin 
Prefect just as Ron is a fine Gryffindor Prefect. They both do a 
great job upholding the traits their individual House's value.