Reagan was not a perfectly consistent conservative, and his term in office the government was not very conservative at all actually, but it's hard to think of any better word to describe Reagan himself. Beirut was one of the best points to show this, in fact - although he at first fell for war party line and setup a foothold in the middle east, it didnt take him long to wise up and reverse course.
The rest of the things you mention are blameworthy but I honestly believe he was mostly a patsy on those, he trusted and believed the wrong people, he didnt ask all the right questions, he was loyal to his subordinates to a fault, and a lot of bad stuff went down on his watch. What you dont mention is that the size of government grew in all areas even faster than under his predecessor, but then again that's blame Congress has to take the majority share in.
Overall I would characterise Reagan as a conservative who had difficulty governing, as a conservative.