Great question @Alex Tran. I'm a big fan of video. I use Vidyard to send personalized messages and it works well.
Some tips when sending:
1. Keep it short (60 seconds max)
2. Use it as a follow-up to email or phone like @Ben Bunting mentioned.
3. Before you record, make sure you know the focus of the video, otherwise you're likely to ramble.
Vidyard has a free course on the best practices (that's how I learned).
Good luck with it. It's worth a try!