Not in any hurry - I have a small hand so the 6+ is definitely off the table, also because I often keep the phone in a shirt pocket - can you imagine keeping that behemoth in a shirt pocket - probably wouldn't even fit in some! Even a pants pocket - yikes... yes, yes, I am happy to see you! (those of my generation will get it, all you younger folks, google Mae West)
If the same trend continues, there will be a 6S next year with a more significant performance improvement. The biggest size increase favors length of the 6 over the 5s which is not that big a deal - I got plenty of space for folders and icons using only 3 pages now so another row is not compelling. I guess it might be nice for having more space available once the keyboard comes into play, but I see no other benefit of the size, although keyboard use is a big part of my usage. Meanwhile, the little over 1/4" increase in width is not going to allow for any serious increase in text readability. As for the faster LTE - that only matters if your provider has deployed the faster LTE in your area. If I were still in Maine, doubtful, down here near Miami, good chance - so that would be nice but I can wait a year since most of my time is on WiFi. Moreover, my home is 802.11N and I have nothing else on AC, so no benefit for the AC on the 6 unless I want to spend another $200 for a new router... and from what I see, most public WiFi is N or, worse, still at G. By next year we may see AC WiFi becoming more common and maybe router prices will start to drop.
So, in my case, waiting for the next iPhone is the best option - besides, I got another year on my contract subsidized 5S - although I see VZW is offering a free trade up... Hmmm!