Having power is good. But if you have good technique you can disrupt your partner’s attempts to generate force or apply his power against you.
This is a 2-way thing in that what you can use against your partner can be used back against you. So you need to be more exact in how you do the technique and apply the power. Then only will your partner find it difficult to fight you off and he can take a trip backwards to make friends with the wall.
After several years, the intermediate training must emphasize the principles learned earlier. This is when the strategy of piercing leg, leaning stroke, angling, positioning etc, stuff from the form must be brought out to play. A good place to test them out is doing push hands. If it does not work then your training partner can help you to understand why.
A shoulder stroke can be a very good technique or it can be one in which you end up eating a knuckle sandwich. So do not underestimate the importance of proper positioning. Once you are in the right place any attempts to counter your technique will see your partner placed in a more precarious position.