It will be very difficult to dump the market further(it is possible, but it will be very difficult and dangerous), because the miners are already working at a loss on some coins, like ethereum. Bitcoin almost fell to mining cost price, so, i think, it worth to start to buy now.
i hope very much that by starting right now we are not runing our chances for pfofit 
then it's a chance that new year will make some corrections, so to predict anything is dangerous