Opera Mini needs to upgrade it's existing features (such as: File Downloading, Web Video Playing/Streaming, Smart Cache Rendering etc)
I suggest to add "Multiple Thread Connection" throttled/accelerated downloading feature for each individual file downloading process. Multi Thread Connection helps to fully utilize the bandwidth to download files with higher acceleration.
Currently Opera Mini's Streaming feature is not that good & speedy as it's nearest competitor UC Browser. UC Browser can handle file downloading & streaming much better than Opera Mini.