of course its not necessary. You can do anything you want within your credit card limit. You will get better scores at lower utilizations though. less than 10% is a good target.
Its just im not sure if its per card or the whole total limit. Cuz I got a card w/ 2500 limit but I use 602 , yhe rest is 0 bal. Amex: 4500, disc: 8750 cap1: 351 dillards: 1800 all is 0 except for the one card.
You are doing well with the utilization. Generally, I mainly keep an eye on total utilization. It is scored both total and per card though... so its possible you could gain a few more points by reducing that card balance. If you have a mortgage or some other big purchase coming up, it wouldn't hurt to try it.
I currently am at 8.77% total util, but have one card that I am going to pay down further before it reports again because I think it will give me a few more points and I am planning on applying for something next month.