I would offer this as a solution if you want to get the most out of tennis - take this with a grain of salt as I'm only relying on my own experience in football and track.
First, your training, as an athlete, should never be BBB. Ever.
Second, your training MUST be more than lifting - you have address agility, speed work and conditioning.
Third, your training, even in the off-season, should have some more skill work.
Periodizing your training during the off-season, for the weight work need not be terribly difficult.
3 cycles of 5's PRO with SSL (5x5)
2 cycles of PR work and FSL (5x5)
So lifting should be 2-3 days/week.
Conditioning/Agility 2-3 days/week
Skill work - min of 3 days/week
Mobility/recovery - 7 days/week
Do not confuse GPP with SPP - in other words, training in the weight room is GENERAL, not specific. Don't mimic "tennis moves" with weights. Tennis, like many sports, is probably on the "Specific, not general" training bandwagon. I see these sports as ripe for someone to step-up and apply these principles. But changing a paradigm is difficult and I don't see it happening soon...or even ever.