Gorgeous Phal!! Aerial roots---some hybrids are more prone to aerial roots than others. Sometimes, however, aerial roots start growing when the potting medium is broken down and the plant starts making them instead of roots at the base. I would check the potting medium to see if it needs to be repotted.
How long ago was it potted up? are there healthy roots at the base?
If everything is ok, then I suppose your next problem is the weight of the phal. Maybe you want to go square as opposed to round. I have a phalaenopsis that is now slightly more than 2 feet across and it is held up by a 6x7 aircone pot.
You also have to think about the potting medium if you are going to pot up. This is something I've been debating for a while for my large phal. I can't go any bigger without seriously considering going with a shallower type of pot because the thing is so huge. So, you need to consider whether your current potting medium is going to work if you pot up, or whether it's going to stay too wet for too long.
Consider putting an inverted net pot in the center.
Good luck--and it looks super duper healthy