I think we're in a massive correction phase, and it will take some time to recover - probably with more sustainable and slower growth then during the crazy months Nov/Dez17, as the bubble has burst and the people will be more wary to buy.
At the same time, I think we'll see the long necessary end of BTC as the single reference currency, and first ETH , then others, will be the motor of growth.

Thus, I think we'll see the next all-time high of market cap quite late this year, around September - let's say week 38.

Needless to say: If I'm wrong and it's earlier, that's fine too ;-)