mmm... I don't see rest periods as waste of time. Having said that active rest(oration) is more effective than passive one (Supertraining is my main source in the subject which states it directly) than I would suggest supersetting your main lifts with active rest drills which facilitate better movement in the main lift (I do it myself). Controlled nasal diaphragmatic breathing is always part of it for me.
While this probably not what you were looking for (standard supersets) but it is using your rest time to improve your movement quality and strength.
Some examples for staff I do (or did recently with success)
Main lift / active rest
Used currently
Deadlift / hanging on a pull up bar + elevated rocking and/or marching
Pull ups / Head nods or elbow whip half rolls, marching if my midsection feels not connected enough
Press, double press / superman marching or Flexible steel style OH arm swings
Bent press / standing rolls or Flexible steel style OH arm swings
Swings / shoulder packing drill
Near past
Deadlift / exaggerated-4-count naked swings
Deadlift / leg shakes and leg swings + windmill (naked or with light load) - this probably have similar effect to the supersets you already do with TGU
Front squat / prying goblet squat (light weight or naked)
Bench press / arm swing, windmill, PNF arm swings
Bench press / light band pull apart
Press / head nods
Probably will test sometime in the near future
Deadlift / bent press (medium+ load)
Swing / bent press (medium+ load)
Whatever/ farmer carry (light weight or moderate weight for non-grip-demanding lifts)
Probably most push/pull supersets will work well. "Reset lifts" seems to work as well even with higher than light loads (windmill, bent press, TGU and whatever other rotating-mid-crossing-head-moving lifts).