A Storm in the Force
The various abilities of force sensitives across the spectrum have this strange correspondence to emotions and weather. From the various Jedi to the Sith, to the new Jedi being brought to life in the new trilogy, and the new dark side adepts like Snoke and especially Kylo in the new trilogy, the parallels between the calm weather like disposition of the Jedi, to the storm-like disturbance of the abilities of the Sith and other Dark side adepts are too good to ignore.
The Jedi of old prized emotionless peace. They preserve life by detaching from it, giving up everything for it. This is noble, but as the weather analogy will show, ultimately fruitless. The Jedi are like a calm breeze, rarely becoming strong enough to carry substantial weight (as expressed in their sparse use of violence). Ideally for the Jedi there should be a calm, no breeze at all. But as those with experience with wind know, nothing stays so peaceful for long. A calm is a blank state, just waiting to be filled, and many disillusioned Jedi often find the Jedi way lacking precisely because of this. Suppression of emotions in order to maintain a calm is like putting a storm in a box: it's impossible.
The Sith know this, and their critiques of the Jedi have one strong point. The Jedi do not make use of their emotions, their stoicism means they are rarely very powerful except of a extremely force sensitive or very knowledgeable adepts. The Sith however do make use of their emotions, and to great effect. The Sith are a storm: Dark, with great destructive winds and lightning (remember force lightning is common for Sith). But the Jedi's critique of the Sith also hit its Mark. Emotions often drive Sith more often than the reverse. A storm will always pass, burning itself out, as most Sith eventually do.
This is where the new Star Wars releases meet both deficiencies head on. In Star Wars Rebels, K'naan Jaarus meets the Bendu, who claims to be beyond Jedi AND Sith. His greatest display of power is in engineering a force storm against Thrawn's army. Those familiar with legends know that the only person to use such storms was Palpatine, who was crazy powerful, and this Bendu claims to be more powerful. In the new films, Snoke says that Kylo is powerful precisely because he is a torturous mix of light and dark. Rey is drawn to the dark, and you'd notice emotions playing a far more major role in Rey's actions than most Jedi would allow.
The last movie of the new trilogy will hopefully make things clearer as to the disposition of new Jedi, who are not stoic like the old Jedi, or an emotional wreck like Kylo, or the Superstorms of the old Sith. But we can already see a running theme, aptly represented in Rose's statement to Finn:
"That's how we're going to win. Not fighting what we hate. Saving what we love."