Laertes, then, is too free. He has an incendiary mind and savagery in his body. Whether or not these are his actual faults (breathed quaintly) or forged ones, is still not clear to me.
I will say that a Laertes struggling to oe’ermaster a quicksilver brain and a body built to break the world around it is a more interesting Laertes than one who is virtuous and checked up on by an overprotective parent. A Laertes who has to fight to keep his temper, who has to work at being politic and civil is a Laertes with demons. That’s a Laertes worth putting opposite the prince at the center of this play.
The Hamlet Project 
Polonius is (also) a rich character; his tactic for getting information seems to reveal data from his youth, which gives a chance to the actor to re-live those good old days -maybe not fully realised but self-energising at the time of this dialogue. (There is nothing in the play, it seems to me, that can be cut off for the sake of a production without damaging something in the play.) And as for the name Polonius, I think it is one of the references to Poland; somebody whose ancestors were from Poland has become a leading figure in Danish Kingdom. -in a way similar to Horatio being from another country. These add a cosmopolitan colour to ‘nationalistic’ power struggles.