This looks like a fun deck. My only suggestion would be to work on the mana base a bit. For example, there's really no reason to be running Tranquil Expanse, a tapland with no upside. There are a lot of replacements such as Temple of Plenty for scry, Scattered Groves for fetching and cycling, or even Graypelt Refuge or Blossoming Sands for life gain. You could also look at bounce lands such as Selesnya Sanctuary, or filter lands such as Sungrass Prairie. Those are just the WG ones, but there are WU and UG equivalents for most of those dual lands.

Some other cool lands are: Treva's Ruins (a good replacement for Seaside Citadel), Soldevi Excavations (scrying for 1 generic), Halimar Depths, and Mistveil Plains (return card from graveyard and then tutor for it).

Thank you for the suggestions 6thExtinction. I think I might have a Soldevi Excavations around somewhere.

I think I'll slot in Treva's Ruins