First off, BBS isn't some supplemental program that you add to your already a "couple times a week" program. Done properly this would very quickly lead to gross over training! BBS should be the foundation of your fitness program.
Secondly, you need to at least use weights. Basic compound movements. Pick 3-5 of them and train to complete failure. 2-3 minutes is way too long for a set. What happens is that the slow twitch muscles start recovering before the set is done because the resistance is too low. Your time under load (TUL) should be more in the 50 to 90 seconds range whereby you'd hit failure in that range. It should be damned hard to get to that TUL and take everything you've got to get there. Your mind should be screaming for you to quit! This is a brutal protocol if done properly!! Dial that in and it's one workout every 5-7 days to start. As you become stronger and learn to train more intensely, you'll need to train even less or progress will come to a halt.