Although I do agree with criticisms of his writing and have felt the same in his later books (as I was too young to feel the poor writing when I read A&D, Da Vinci Code etc.), I know that I'll get his next book when it releases.
I like that his works mention random things that you can then read about from other sources, information that are tangents to search off of. It helps that all his books are easy page-turning reads.
But yeah, about his writing, I remember the latest (Origin) having some atrocious lines
If you want to read a good non-fiction on the Sri Lankan civil war, check out "The Divided Island" by Samanth Subramaniam.