Here I am finishing up my Syllabus for teaching this semester and I am already being hassled about teaching in the fall. I don't have anything that I am responsible for in the fall, so my options are either to design my own course or teach an existing one. By "teach an existing one" I mostly likely mean teach a section or part of a section of the mega intro course. There's pros ad cons to both.
Teaching my own course would mean that I could control all the content and teach only what I want to. It would also mean that I would take on fewer students (probably 30ish). BUT, there is a push right now avoid developing specialized advanced course, and instead target new courses at hooking freshman into science. Therefore, I would be building a course that would be taking research from my field and applying to what freshmen understand. On the surface this sounds easy, but in practice it might completely suck.
Being propped up in front of 300 or so students to teach an intro course is not my idea of fun, but the material is all laid out already and it would require 1/10 the preparation. I also wouldn't have the grading to deal with that would result from a smaller course and it would tick the "taught a big class" box in the departmental mindset of what people need to do before tenure. This is not something I feel I have to check off at this point, so this is a minor advantage.
Having not taught either type of course, I don't know what the time commitment is for each, but I would assume that the larger course that is already laid out would be less. Thus, I am tempted by the path of least resistance on the teaching front. OTOH, a smaller course of my design would clearly be more fulfilling and make the Dean happy because it fills the New Teaching Mandate that is being pushed.
Maybe I'll flip a coin.