You aren't addressing Apple here. We are all users like you. Apple's policy is that you can only get a refund within 15 days after purchasing additional iCloud storage. If that applys to you see Roger Wilmut1's post here: https://discussions.apple.com/thread/4491639?tstart=0. Otherwise you can downgrade your storage and you will revert to the free 5GB plan at the end of your current plan year.
The "issues" you've raised are nothing to do with the iCloud service.
No service that uploads data allows you to disconnect the device you are uploading from while uploading data. Doing so would prevent the upload from completing. It is a basic requirement for any uploading service that you remain connected to it for uploading to be possible.
The time it takes to upload data to iCloud is entirely dependent on how fast your Internet connection is, and how much data you are uploading. Both of these things are completely out of Apple's control. Whichever upload service you use will be affected by the speed of your Internet connection.