I think your choice right now is good as is. Pick XLM and DGB I think they are the most profitable among the choices. If you will see a good selling point before a year, then don't hesitate to sell. The only advantage of holding at least a year minimum is that it will maximize possible profit. Nevertheless, it also can somehow maximize loss if things turn the other way around but the bright side here is that if a coin you pick is one with lots of potential to survive for that long, then it can somehow gives you a chance to gain a hefty sum of profit just by waiting.