I am not sure when you switched to CloudFlare but it does not seem to help the cause. I hope you are using the business or enterprise edition because pro/free versions are not really suited for a size as big as Imgur.
My issues with Imgur are basically these two:
My dashboard does not load the images in my account 9 out of 10 times. I have to reload the page and hope that it would process and show me the recent images. I understand that I have way too many images in my account that might be causing this issue. I even mailed Sarah to switch my Pro status to a brand new account so that I can start with a blank account. It is not done yet.
My second problem is the reliability of the uploader. It was unreliable before skipping around 2-3% of the images on large bulk uploads. It is now horrible because of the site unreliability. I prefer to use a third party app (ShareX) and I get a failure rate of around 10-15%. It is a major headache considering the limitations on API powered apps.
I hope you are doing something about this. I do not expect priority access because I am a paying customer but downtimes like these are really messing up the joy of using this fantastic service. Do not make me look for alternatives.