Two things you could add to your workout are paused reps and eccentric reps. Both of these are typically done using free weights.
Paused reps are done by pausing all momentum at the bottom of your exercise. Ex: bar touching your chest on a bench press or bottom of a squat before standing back up. This adds more time under tension which increases muscle recruitment and builds more muscle.
Eccentric movements are controlled movements along with gravity. Ex: lowering the bar to your chest on a bench press or lowering into the bottom of your squat. Use 3-5 seconds to control your rep to the bottom before accelerating back toward the top of the rep. The eccentric phase of the movement is your strongest portion of the exercise and the best way to build muscle.