Why would it delay habitable settlements in any other case except when they're right next door? If they're 2 systems away, you'll still get them before your Colony Ship is ready to settle down, and if they're further away, Influence will be your timer no matter what choice you make.- Delaying your guaranteed habitable settlement. Usually you should be able to have it touching down by 2203, if playing an origin with such habitables at least.
You'll easily get that information in either case though. The second, third and fourth Science Ships will gather it long before you actually need it.- That additional information which will guide your play. (How much free space do I have? How close is the nearest genoicidal?)
This I don't really understand. Finding those contacts further away from you is so far down the line, by then you can have a dozen or so Science Ships flying around if you wish to. Whether you locked the first Science Ship into Assist Research or (for example) the fourth one, has next to no impact on the amount of information you will have collected at this point in the game. It's just ~a year of information not having been collected by one ship, compared to a decade of half a dozen or more ships flying around.- If playing the proactive first contact, the influence you can get from sending science ships as far away as you can to get as many first contacts as possible to farm influence. I'm particularly fond of this on my recent voide dweller plays.
Realistically, both paths likely don't have much of an impact on the overall game. It's a few months of extra science at a time when you're not producing a lot yet vs. a few months of extra exploration on one ship. Both become completely insignificant once you starting pushing out science ships and spamming labs.