I have been a member of this subreddit for about three weeks now, and I have to address something that is bugging me a lot, and that is the requirement that Warp capability (or other equivalent) is absolutely necessary for First Contact with the Federation. As far as I know, there were many instances in Star Trek that put First Contact on the forefront of exploration, such as Captain Christopher Pike's contact with the Talosians of Talos IV (TOS: The Cage).

It is rather how one becomes a member of the Federation that is at play here.

According to TNG: First Contact, a prospective member of the Federation has to exhibit an "advanced level of technology", which the baseline has evolved to Faster than Light travel.

So while Faster than Light travel is a key for membership in the Federation, it shouldn't be the baseline for First Contact with a non-member planet. I would argue that it is the Prime Directive that should govern Starfleet's conduct with planets that do not possess the capability of a Warp Drive.