Iron Fist is going to be the last season, and the last Defenders character to be introduced before the Netflix portion of the Marvel Universe has a super team up. Finn Jones has a lot riding on his back because of it too.
Showrunner Scott Buck doesn't seem too worried about it though. Speaking to CBR at NYCC, Buck talked about why Jones brings something to this universe that isn't there yet. It seems the range and youthfulness of the portrayal were key. He said:
You know, we saw him and I think we all just knew immediately this is our guy. He's a slightly younger character than the other Marvel heroes, and there's a youthful optimism to him that Finn himself seems to generate, but — underneath that all — there's some serious badass attitude that can come out. He just seemed to be able to display all that when needed and sometimes all at once, so he was very capable and flexible as he brought the character to life.
Iron Fist is going to be a key part of the puzzle for the Netflix shows, with a lot of foreshadowing done in other seasons about what we can expect him to be dealing with. Hopefully, it all comes together to give us a strong lead in to The Defenders. That would sure be nice.