He didnt seem to show any pain, more anger that Drax had laid hands on him. I see what you mean about him taking Drax more seriously after that though, but I thought that was just because Ronan had gotten bored at that point. I just they would have shown that if Drax was sober he would have been a threat to Ronan, especially without Ronan having the gem. It would have been easy to portray as well, just have Drax land one punch that sends Ronan flying, then after that Rona just beats him by dodging his punches. They could still have had the scene at the end of Ronan manhandling Drax in the ship as Ronan had posession of the gem at this point. At the start of movie he accross as bad-ass, it was just later in the movie he didnt. From Knowhere onwards he just didnt seem that poweful, even Korath was throwing him about in their fight which just shouldnt happen in my eyes. Apart from the prison scene he didnt really live upto the name Destroyer. And as someone who is something of a rarity on here, i.e a big Drax fan, I found that a little disappointing.