Not sure what you are looking for, but I can tell you this: If you make to radical a change from what got you to where you are now, you will lose what you have worked so hard to gain. I see it happen all the time with guys I used to compete with.
They would train heavy with basic movements all year and then come show time, switch up to isolation movements, machines, etc. They would lose mass so fast they couldn't figure out if it was the diet, training, or cycle. I recommend you continue to train with what you have been doing, remove one set from a couple exercises to add in one isolation exercise per bodypart and hit it.
Ex: Offseason Chest:
3 sets bench
3 sets incline
3 sets flys
Contest time:
3 working sets bench
2 sets incline db
2 sets fly
2 sets cable cross-overs
That is just a flippant example but as you can see, the total sets stay the same, you just added one isolation exercise but did not increase your total workload.
Be very wary of overtraining at this time, when you are dieting, it is easy to get injured from fatigue, less calories, strength going down and more. You just have to train smarter, not harder.