Good advice here. Honestly the way I do it though (just a modification to the rule about different genre videos each day) is that I will usually do 1 review video for a newer game, then I will do 1-2 podcast type deals (which have video footage from games i'm referring to but still not a review.) Now the key is like in my Final Fantasy 7 podcast I did two videos. Both were two different subjects about that game but they were both originally podcasts. The video footage is just there to supplement it.
Therefore by doing that if you want to have a podcast or rant series you can without it being too different from your reviews. This strategy would keep the fans happy either way but you can have diversity instead of having to constrain yourself to 1 let's play or 1 game at a time. It also opens up the doors for you to be able to make more complex videos that take more time, but it's not just random filler. Just my 2 cents.