It's a tricky question really.  One could make an arguement that the TB's are basically to cover your own butt, essentially being your rear tubes.  Of course you can use them to force an enemy sub into a mistake as well.  But in general that takes a lot of complexity and mastery where you're already doing a lot of things at once.  Some just opt out of it and pray no sub gets behind them.

It depends on play style and multitasking ability. Strategically, they can be launched early and used to try and sink ASW ships or escorts that could pose a problem later, but once you're actually in a fight, they're usually just one more thing to keep track of and not worthwhile unless you're really good with juggling between them and regular subbing.

As for which supports to put on instead, Engi and Rep are your best friends, in that order.