when you get a certain number of dips, do weighted dips (either a DB between feet or preferably a belt).
With the BTNs i'd use 5x3. I havent done them heavy, but heres what people who do do them heavy told me. after a few reps form gets sloppy and you can mess up the drop. therefore i'd keep it pretty low rep. start with these really slowly man (and while your working on form/using low weight, maybe do a few heavy sets of Push Press (regular front PP) and really push the weight high with these to get a good workout).
I <3 front squats