Video Clip Sizes

Question, I’m uploading a video gallery for a friend of mine and wanted to know the recommended way to do this. The easiest way would just be to paste vimeo links into a grid. The only problem is that these links come out at different sizes. The other option I’m seeing is to create video light boxes with styled thumbnails. That might look better but I wanted to know if there was another approach I was missing – perhaps background videos in grid elements? Also, with video embeds, is it possible to have the videos auto-play on rollover?

Thank you!

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