You are correct that trumpet vine (Campsis radicans) is a sun lover!!! A wonderful plant for attracting hummingbirds also. It is slow to come out of dormancy in the spring, and can take a few years to establish itself and produce blooms.

Campsis radicans blooms on new growth, so cutting it back in the fall should not affect its bloom the following summer. You could try not cutting it back this fall and see how it does next spring. You may experience some winter dieback, but you can just prune that out once the vine begins to leaf out and you see if there are any dead stems with no leaves.

Once this plant is established it will tolerate drought to some extent. You may try a spring fertilization using a fertilizer with a higher middle number such as 5-10-5 to encourage blooming. Phosphorus (the middle number) is the nutrient that encourages flowering. Do not overfertilize or you will experience foliage at the expense of flowering.