Oda ignored Elbaf until now. No reason for going to there now. Nothing to do there. Move on Lodestar is the next goal.
Oda didn't ignore shit:
1. A mysterious tree still to be revealed.
2. An army's kingdom labelled as the strongest in the world still to be revealed; said kingdom remains a mystery too as we've only seen a village from the suburbs at sea level.
3. Loki still silhouetted.
4. Hajrudin, a main ally of Luffy, being the person who rescued the books from Ohara and who dreams of becoming the king of all giants; in spite of Loki, that guy still to be revealed, being the current royal.
5. Kid currently drowning in the sea around Elbaf.
6. Usopp's dream of visiting Elbaf still highlighted.
7. Saul recently revealed to be alive and in Elbaf.
8. Vegapunk intending to travel to Elbaf with the crew as they leave Egghead.
How can you seriously state there's nothing to do there?