Yes, I'm scheduled to go over the 16k channel count. I was going to rechannel so that it is all on the same controller, but couldn't all be on the same hub since it's over 4096 channels.
Last season, I had 16 strings all starting on the ground headed up, but I'm still debating whether to splice another 50 onto the end and go up and down like you are talking about, or just setup 16 more controllers. I had a few strings die last year on my mega due to heavy icing that occured. The rj45 pigtail connectors actually corroded down to nothing from the moisture! So this year I am going to try to sheild them a little better from the elements. But was leaning toward just having separate controllers due to ease of replacing and if one goes down its not such a huge dead spot in the tree.