I doubt that Archer exchanged maps with a new species he did not trust but your point is nonetheless correct, space is disease and danger wrapped in darkness and silence. If they had stayed at home the war with the Romulans also wouldn't have happened and the Federation have emerged.
This was the beautiful thing about Enterprise, humans and Vulcans were both correct. Humans aren't ready yet to go out there, they never will be, but once they are out there they also create something marvelous like an alliance among species who have a history of not getting along.
In the 3rd episode, before he even got a response he'd sent out Earth's location.
[FONT=Arial, Helvetica, sans-serif][SIZE=2]ARCHER: Run this through the translation matrix. My name is Jonathan Archer. I'm Captain of the Starship Enterprise. We're on a mission of peaceful exploration. Oh, we come from the planet Earth. We're sending you a pulsar grid that should help you locate our star system. Did you rotate the frequencies? [/SIZE][/FONT]
So... yeah, that just always struck me as a bad idea to say the least. In the Terra Prime episodes they were complaining about this too, so one would assume it was general practice for whatever reason.
It was a catch 22 though with the Vulcans and humans both being right. On the one side... especially during the first two seasons, Archer and company... just so often woefully seemed out of their depth the way the bungled around through the various situations of the week. On the other hand, it's a valid point that the Vulcans, Andorians and Tellarites otherwise formed a hate triangle that it took the humans to break up and be the happy go lucky friends they are later on. Though I guess there's no way to know how things will turn out if Earth wasn't involved, it's entirely possible they could've put their differences aside themselves. Go back in time to the early 19th century and tell someone from America that Britain would be their strongest ally in the future and they'd call you crazy probably.