At first I was very excited to see the sentry mode videos, but as you said, it can take a lot of time. So here is what I've been doing:
1. I have 2 USB drives. I've got 1 plugged in and 1 in the console as my spare. They are 128GB so they last weeks before they fill up.
"Sandisk CZ48 128GB USB 3.0 Flash Memory Drive - SDCZ48-128G-U46". When 1 fills up I swap the other one in immediately.
2. For expediency sake, I figure if there is no damage to my car (yes, I'll walk around it and take a look at it), then I don't need the videos.
So I will delete the videos from the filled up USB drive after this review of my car's condition. Then the drive goes back in my car as the spare. This approach could be modified to add another USB to the rotation so you could "sit on" the videos for a couple of weeks in case you later realize you want the videos. That way you never delete any videos newer than 2 weeks old, for example.
3. I use a web app to review my videos when something happens that I care about (e.g. I have provided videos to the county sheriff's office when I was right behind an accident that occurred. This was a case of using the "recent videos", not the sentry videos). This web app is pretty darn good. In fact, I liked it so much I sent in a donation after using it yesterday:
TeslaCam Video WebApp Player
I think some people are reviewing sentry cam videos every time they get in their cars, but I don't actually want to do that.
Hope this is helpful!