Every genre of novel can benefit from an increase in suspense and tension- from external tension, in thrillers, to internal tension, in romance. Tension and suspense are inextricably linked to conflict. One of the reasons we need conflict in fiction is to create tension in the reader.
Tension is a state of heightened alertness. Suspense relates to what is to come-the promise of future conflict. The more obstacles the protagonist faces, and the greater they are, the more tension is created. Obstacles could be internal or external e.g. a lack of confidence(inner), or a villain the character must defeat(external). These obstacles should be directly related to the character’s goal. The outcome should be uncertain.
Another aspect of tension and tension is reader empathy. To build both, it is necessary to make the reader care about the main character- if they are invested, the tension mounts up. In my own writing journey, I had learned to create reader empathy. But I didn’t know why I was doing it. Now I know that reader empathy is crucial to creating tension and suspense. There are a number of techniques to build an emotional bond between character and reader e.g. put your character in jeopardy or make her excel at her job.
As regards tension and suspense, stakes are also important. High stakes increase these elements. More than that, a strong chance that your protagonist will fail helps.
Creating tension and suspense in your novel is a worthwhile endeavour. These factors will improve any novel, from the action packed to the more introspective slow burner.

I’m wondering if authors that carry a lot of empathy as a core strength are able to write with empathy more easily?
Thanks for your comment, Nancy. It’s an interesting point and I’d like to think so. These techniques are simple methods that anyone can use to create reader empathy. However if the author is cold and emotionless, then perhaps they might not feel natural to them and this could be where a capacity for empathy would be helpful. It seems empathy is highly regarded both in real life and in fiction!