LOL while I appreciate the comparison... LotR is in some ways way more "lego" friendly than Dune. For one thing it has huge set pieces described in aching detail which just screams "build me." And a lot of it was fairly family friendly.
Dune.... not as much.

Oh I can't wait for the lego set of the Honored Matres sex house! Or maybe we can have a Leto II and Ghanima incest marriage set!
(yeah yeah I know it was technically political only) God-Emperor Worm Leto would also be a trippy lego set.
of course bob won't be happy until the Fish Speaker lesbian set is released.
EDIT: I just now realized Leto and Lego are 1 letter off.
All hail God-Emperor Lego II the immortal!