You should probably prioritize. Whatever area you are lacking will draw your attention and focus most, so you could start with that. As long as the intentions are not too all over the place (so that you can take action for multiple intentions), having lots of them probably does not hurt. Even if you can't focus too much on certain intentions, it is probably helpful to create them in your head, write them down in your journal and pay visit to them once in a while to see if there are any opportunities to manifest them.
Another interesting way to look at this is to question where intentions come from after all? I believe all intentions are meant for your growth one way or another. Therefore, whichever of your intentions need more focus for your growth in the now will possibly start manifesting first. So you set your intentions (goals, targets, etc) and see which ones you can take action right now. Also look out for signs to see which ones look like might have a chance to manifest sooner. You will get clues sooner or later to point you in the right direction.
One thing you don't wanna do is get frustrated, run around like a chicken with its head cut off and eventually get yourself stuck.