You can enter whenever if your opportunity skyline is long as BTC will never disillusion you in the event that you hold it for long-term. This defeat was arranged and the individuals who says that BTC have no esteem, buy gigantic amount of BTC in its ruin. At whatever point a major drop comes in BTC, it generally hit new high after that fall.
The best time to invest in btc is now as long as you want to hold for a long time. I see ethereum as another excellent investment at this period since the market is very long, expecting a bull run soon. projects like linkchain's LNK token will be an excellent choice for investors, with their ico2.0 coming up in Nov. 11 Besides, i thing anyone investing for short time gains should better trade instead
Naturally, it would be better if you invested in it a bit earlier when the cryptocurrencies' prices were less. However, now, it is also not very late to do it, brother.