Eh? People spending more time on a site is actually a good thing. Don't just see length, see the actual content. When I started Hardware BBQ, it was about 89%. In a year, it has reduced to 74%. Adding news and later guides helped to reduce the bounce rate and increase average time on site and increase pageviews significantly. I've added Xenforo forum to build a community, but that's going to take a while. I have more ideas for that too. Later I added a database section which did its part to some extent. If you're sticking with one type of content, higher bounce rate is bound to happen. Anyone is doomed to failure, no matter how big the website is. The same advice is given to a lot of people, not just you. Something that the so-called SEO experts will never advise.
The point is, you'll always have to keep adding or else you'll be left behind.
When you check out websites like Anandtech or Android police, they don't just provide reviews and news, but guides too. In-depth and relevant content help users to stay on the website stay on the site longer. Same goes for GSM Arena. Some websites even have a separate section that lists phones, images, specification with comparison option and also amazon affiliation. Keeping users engaged under one roof helps to reduce bounce rate and increase average time on site. Indiblogger itself is a big example. They don't just act as a place where you submit content links, but also has contest section, forums section, chat on the site, etc.