For something like numbers, it would be a good idea to include the kanji. Also, if you can't get a native speaker pronouncing the numbers in Japanese, still include music. The video becomes stale and unwatchable without something.
I still think you should include some kind of viewer interaction - like a quiz at the end or something. Otherwise it's basically the same as learning from a book, or cue cards - making the whole idea of making a video in the first place redundant.
People learn Japanese in different ways. If people are looking for a video, they probably want to see something more engaging than what is typically found in textbooks, for example. The most successful Japanese learning videos (in terms of engagement, and actual learning) that I've seen come in two forms: 1. An actual lesson - like one you'd find if you took lessons - just in video form (the best ones often have native speakers). or 2. A different form of media - such as a song. A song about numbers in Japanese could be very effective here.
If you want your videos to stand out from the crowd you need to do something different. Having a video with no sound and just the words won't be engaging - considering the already diminishing attention span in modern day.
In short, to improve on what you can do today, I recommend adding these: 1. Sound, like before (try to get pronunciation) 2. Add kanji again (just remember that hiragana is the main-focus for most learners at this point). EDIT: 3. Also, you might want to add alternative readings for the numbers. For example, よん and なな for four and seven, respectively.
Also the title page is missing the plural "s". It should read "Learn numbers in Japanese".
The numbers in kanji is really important because so many of us who learn Japanese go to Japan to be ALTs, and some of those schools write the entire schedule on the teacher's room board in kanji numerals. I am quite familiar with them yet they are STILL a headache! The earlier the exposure, the better!
I suggest that when you switch screens for the same number with the arabic numeral gone on the second frame, in its place put the kanji numeral. If you still want to change from 3 lines to 2 lines on the frames you might just have the kanji and the pronunciation in roman letters and take away the kana on the second frame.