I haven't had a single dick-pic 
(almost disappointed)
I've done match 3x, each time for about 2 weeks - I'm currently 2 weeks into my third stint.
First thing that struck me coming back to it after 18 months was just how many people are still on it (or possibly like me, on and then off). So the gene pool is actually smaller than you think, there's a whole load you rejected first time round!
My main irritation with it are how few men seem to be able /willing to carry a bloody conversation!
I almost always ignore "hi" and "how's your day" and "how are you finding it on here?" as an opener. It's soul destroying and pointless to send huge personalised messages that get no response, so I'm fine with a one liner. But is HAS to reference my profile in some way. Minimum effort!
On the rare occasion I've responded to a "how's it going?" approach, I've found conversation has stalled PDQ.
Each time, I have found myself thinking "well, maybe it's hard to converse with someone you don't know?", but then after a while, someone comes along who is on your wavelength and can string a sentence together! So my tip is - it's OK to be picky and wait for that person!