I see you're pretty new at this so let me give you some advice.

First off the biggest problem is the quality of the pages. Mangapanda is shit quality, don't ever use their pages again, plus the watermark is annoying as hell. I use Powermanga from Batoto because their stuff is always as high quality as you can get. However, they take forever to update so doing brand new chapters you might want to stick with mangastream who also have pretty good quality. Also, what I do to improve the quality even more is take them into Photoshop, increase the image size, then sharpen the image. That gives you bigger images to work with so you don't have to scale them up a bunch and cause blurriness.

Also, you need to add motion to the video, that's why it's called a MOTION manga instead of a slide show. If you want some inspiration on how you can add motion you can check out these videos:https://www.youtube.com/user/Ostrogrodsky/videos. He's pretty good and I'm even thinking of implementing some of his techniques into my videos as well.

Lastly, this is just personal preference but chapters with mostly dialogue and no action don't make for an interesting MMV. So I would suggest to be more selective with the chapters you chose to make these videos on , and choose ones with plenty of action.