I wouldn't get too fixated on "points" - there's a lot more to a position than just the material imbalance. There's positional considerations as well - so for example, a rook trapped in the corner with no moves can hardly be said to be worth five points.

Same goes for a trapped N on the edge etc etc

Boo!  

This has transposed to a Four Knights Game alright - usually reached after 1. e4 e5 2. Nf3 Nc6 3. Nc3 Nf6. But the name isn't hugely important.

Maybe an immediate d4 would have been slightly better, opening the position up. But this can't be bad really.

This is the most common variation, but 4. d4 is also good, leading to a different type of game.

Rubinstein Variation, my favourite move here as it creates an interesting imbalance. The main alternative is the symmetrical 4... Bb4. White shouldn't take the e-pawn, as Black regains the pawn with a better position after 5. Nxe5 Qe7.

A book gambit. This time, Black accepts that White can go a pawn up, but Black will gain development.

Nxe5 is the main line.

You were black though - did you have a reason for being unconcerned? Were you right to be? When white nabs that pawn in openings like this, usually he can count on losing the e4 pawn in return. Though I'm not sure in this case - I think black ought to have protected. With the d-pawn pinned, a knight exchange may be the best way of protecting the e5 pawn.

7... Re8 is tempting but doesn't work: 8. Nd3 Bb6 9. e5 and the f6 knight is trapped!

It also blocks the d-pawn, cutting out some support for the e-pawn and blocking the DSB. Not major issues really - the e-pawn can be defended by Re1 and the DSB can develop to b2 - but I don't see there was a need to play here; it's an ugly square for a piece more often than not.

moving the f pawn to f3 would only lead the immediate loss of that pawn as black Night d4xf3 creates a check with the c5 Bishop

It's a double check, which is important - white is forced to play Kh1 and can then get the knight back to safety.

He wouldn't bring the knight back. 9. f3 Nxf3++ 10. Kh1 Nxh2 11. Qe1 Nxf1 wins exchange and two pawns. Much better than going for the a1 rook, winning exchange and one pawn but leaving the knight trapped on a1 -- if White can pick it up then material is close to level.

Interesting! Is it worth it I wonder? Certainly white has to accept...

So what's black threatening here? I think the most direct is Qc8 and Qg4#. White's pieces are indeed completely on the wrong side of the board. If white tries to defend the mate with 11. Ne2 Qc8 12. Ng3, then Qh3 is mate next move anyway. White doesn't even have time for NxB, with the idea of Qe3 to kick the other bishop - because he gets mated anyway! So this is where the points system is hugely deficient. About its only relevance here is that white is a piece up and so can consider sacrificing a piece back if he can hang on as a result.