The second half won me over
I watched the first hour or so, and I didn't really like it. Then, almost a week later I got to watching the second half of the movie, and somehow I was able to very much appreciate most of it. It had several great laughs (including self-referential jokes about RDJ, Cheadle and the MCU as a whole), the action and effects were top notch, and I really liked how it set up some of the later MCU movies.