I don't think there's anything inherently wrong with taking a sparsely plotted novel (like The Hobbit or Foundation, both of which have a lot of details happen off-stage and sometimes bafflingly so) and fleshing out the details.

The problem with the Hobbit movies is just that they did that very badly.

But that's why it would be such a great miniseries. You should use the novels as a framework, and allow showrunners to get creative fleshing out the characters and plot details. The Novels are pretty short, but dense with plot and ideas. A direct translation of the source material would be bad but the potential is there for a great adaptation if characters are more fleshed out.

There is precedent.

Look at Altered Carbon which got 10 hours for the first book, or The Man in the High Castle which was adapted into 2+ seasons for a book that's only 240 pages.