I know most people won't appreciate such a wish and for full disclosure I own cryptocurrency too so it might seem counter intuitive for me to make such a statement but we are at the ridiculous point now where the market is so ridiculously over saturated that most coins do not stand out and it is neither beneficial to the technology nor to the investor to have so many what are evidently scam coins.
We have seen the proliferation of so many coins in fact that it seems that more new coins are added almost on a daily basis. To the extent that coins are now being bought on the strength of their name. We have the continuous deluge of new ICO's which are being shamelessly promoted by the youtube channels for the simple reason that they stand to gain monetarily and the more insane this bubble becomes the more it will actually hurt the long term viability.
A sustained crash now would flush out many of these scam coins, deter others and would lead to a case for stronger business models. It would also flush out those are buying as an investment versus those that are in for the short ride hoping to make multiple fold gains in a few weeks and then dumping en masse. The likes of chaincoin are just the tip of the iceberg in this respect.
Moreover as we know from investments the more parabolic something goes up, the faster and harder it falls. For those currently on the sidelines I am not stating you shouldn't jump in any time soon but I would advise you to cautiously put in a little at a time especially when you hear the level of hyperbole being spouted by the sales people who are masquerading as "experrts" and "analysts" are concerned.