Try E.R. Eddison’s “Ring Ouroboros” and “Fish Dinner in Memison”. He published before Tolkein.
Huge fan of the series. The original is fantastic, the movies are garbage, the miniseries not totally awful.
I found all the books written by Frank to be interesting they were vehicles for looking as different aspects of technology and genetics wrapped up in politics.
I really enjoyed the 4th book God Emperor of Dune as it examines the ‘choice’ God has to make on the topic of free will.
I have read the prequels supposedly taken from Frank Herbert’s notes. Writing not at the same level at all, There is a Trilogy that gives the background of the players in Dune, and how things evolved to the situation where House Atredies is going to Dune. There is another trilogy that explains the Butlerian Jihad and the limitations placed on Computers in that world. Then a set of novels that take up where the Frank Herbert books end to ‘finish that story not written very well but of interest to see where Frank Herbert was coming from.