Make up your mind
The APS-C is much cheaper, but since the sensor is smaller it also has less sensitive pixels. The full frame is more sensitive as the sensor area is larger which helps when there is not enough light. However for most cases, an APS-C camera is more than enough. Since most professionals use full frame cameras, the lenses for full frame cameras are usually better.
What the reader wants is a clear path to follow. Start with a point, explain its strengths, point out its weaknesses and move to the solution you suggest. Do not change your mind during the narrative. So the above could be one of the two. Notice that both make their points and move on.
The APS-C is a cheap solution which in most cases is more than enough. However since the sensor is smaller its pixels are less sensitive, and the full frame cameras with their larger sensors have a clear advantage. In addition since most professionals use full frame cameras, the lenses for full frame cameras are usually better.
Be a guide, do not get lost in details
Your job is to explain your point, just like a guide in a city. You can take a detour, or take different paths, but do not go back and forth the same streets and run around like a headless chicken. There will always be pros and cons about technical choices, make up your mind before you write, not while you write.