I recommend you get a large amount of storage on your ipad. External storage isn't as integrated as on a computer. You may run into copyright restrictions if you put the video's on an external device. Some apps are simplified versions of the computer one. Many apps are a lot easier to use on the ipad.
You can do want you want if you do not mind experimenting around and accepting some compromise.
You might want to consider buying a used iphone 4s which is capable of running the latest ios and see if you can do what you want. Get a sprint iphone 4s and sign up for 200 minutes of free talk time with freedompop.comAirstash
"Easily access, transfer, and stream your files from AirStash® – the pocketable wireless flash drive for iPad, iPhone, and iPod touch! This app requires an AirStash device in order to work. View, import & export photos, wirelessly stream videos, music & podcasts, and view documents stored on your AirStash. AirStash+ is an enhanced alternative to the built-in web interface adding features only possible with a native app." www.airstash.com/
SanDisk " SanDisk Connect Wireless Stick is the flash drive reinvented to work with both your computer and your mobile devices."https://www.sandisk.com/home/mobile-device-storage/connect-wireless-stickSeagate Wireless portable hard drive
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suggested by seebluewww.dpreview.com/forums/thr...Kingston Digital MobileLite Wireless Flash Reader for Smartphones and Tablets (MLW221)
Kingston Digital MobileLite Wireless Flash Reader for Smartphones and Tablets (MLW221)FlashAir™ II Wireless SD Card series
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