Tradeoffs between transmitting and listening with low-power 2.4GHz
Your question is unanswerable without the costs of the various tradeoffs.  You give a relative cost of transmitting and receiving, but have provided no guidance on the cost in your situation of using the RF link.  You have also not taken data errors into account.  Those mean a message is lost, which may cause retries with their associated costs or perhaps lack of features with their own associated costs.

This whole thing is a cost/benefit analysis.  Only you can make judgements on some of the costs, especially when they aren't the same physical quantity.  For example, we have no way of knowing how much you value not interfering with other RF communication versus battery life.

This is the kind of thing where Monte Carlo analysis can be useful.  You set up a bunch of probabilities, write simulations that model all the various interactions, then measure your various costs as a function of parameters you can tweak.