I have set my longer term holding goals for the year 2020. I don't think that we will see anything very, very serious happening in the Bitcoin community before this year, or at least close to this year. This thing just needs time to develop properly and for the people to gain trust into this technology.
Also, the year 2020 is as well a year of the next halving so many things should be happening by then.
I think that holding even 50, or heck even a 25 bitcoins should bring a nice fortune to its holders after a year 2020!
Mark my words!!!
21 should do it. There will only be 1 million people that can own 21, in fact less due the lost coins (the supply will be less than 21) and the total coins will never be mined on our lifetimes, so by owning 21 you are part of an elite of holders. Of course, you are not a monster whale like the super early day guys, but it's a great achievement and should put you on retirement early.