Sharpe's Devil
I personally would like to see Sharpe's Devil as a next (and final) Sharpe movie. The movie should feel like Sharpe's Justice where Richard headed to Yorkshire and was not so much about army and war. And in chronologically it would fit too, since Sharpe's Challenge is in year 1817 or so and Sharpe's Peril a bit later.
The movie should begin with Sharpe returning to England from India and given a last mission to go south America. And also he should find about about his daughter Antonia as a subplot.
Here's link to wikipedia about the novel. I haven't read the book, but the story feels quite interesting and definately have some good material, though screenwriting and editing is needed to make it fit in.
http://en.wikipedia.org/wiki/Sharpe%27s_Devil_(novel)