Both are great cars and they are both made in Japan. I do prefer the styling of the Rav4 (but looks are subjective) and you do have the ability to plug in to charge the battery. Venza is more luxurious with a sort of a Lexus-like interior, whereas is the Rav4 is more about Durability than Luxury. it really comes down to your personal preference. I personally would buy the rav4 prime because it's faster (0-60 in 5.7-5.8 s) and better looking but the Venza is a great option too.

To my mind, no one can give you good advice on this until you're clear on what you need from a vehicle and how you're intending to use it (and why a Prime rather than a RAV4 hybrid). 

There's a general saying that "quality is fitness for use." What patterns of use are involved here? What do you most value in a car? 

Give a bit more detail, some context about place and use, and about what you value the most, and perhaps folks, including myself, can answer. 

TBH, those two are almost the same car. They are built on the same platform and share many of the same hybrid technologies. 

The difference is the ability to charge the vehicle with the RAV4 Prime.

The other difference is that the Venza has some fancy aesthetic features, like the optional panoramic roof.