Sell yourself!

Isnt the 1st message supposed to leave a good impression, isnt it a way of selling yourself? I dont mean in that way,! Surely its similar to a cover letter to go with your CV, get them interested enough to offer you an interview or in this case a date.
Having just logged onto one of my accounts, I'm greeted with 3 new messages. First one is from a guy I've been chatting to on & off for a week or so, have music in common, so chatting mainly about that. The other two messages are new. One saying "Hi", that took so much effort I dont think I will bother replying, hey if you cant string a sentence together on the internet well we are doomed from the start,
The other message said & I quote " Hi, you look like a good un"!  What the actual f@#k is that supposed to mean, am I meant to reply to that, am I meant to be flattered to hear that I look a good "un"? What even is a good un?
It did however prompt me to read his profile & checkout his photos, but only to see if there were any redeeming qualities to this man as his introduction line is from the murky depths of the  " I kinda fancy this gal but not quite enough to make much of an effort" pile.
Even the really cheesy pick up lines are more imaginative than that, just! Guys do really still send "Get your coat you've pulled',  & one of the most ridiculous lines " I must be a pirate, coz I'm digging your chest". Oh how I laughed.  Well actually it was slightly amusing & of course had to be said in a Captain Jack Sparrow accent.
I'm afraid the "Good un"  will be discarded in the uninteresting category & message deleted without reply! Oh I'm harsh I hear you shout, nah just saving myself from more cheese!