A team build doesn't count as strategy, strategy is predicting and every good strategy involves switching. Do what you want man but you will find the good players will hate playing your gym, and the outcome will be decided on who has the strongest Pokemon instead of on who made the better predictions and really skill won't come into play at all, which for you won't be happening since most fire types iare pretty sub par.
I really mean no offense by any of this, but it really seems like you are trying to take an easy route out expecting that your team can just walk through opponents so easily. A Life Orb Starmie will be able to wipe you out alone.