Lands plays almost no blue mana sources, so Carpet of Flowers won't generate much mana off their Islands, but it still functions here as a way to accrue incidental value if they ever crack an Island-producing fetch or dual; more importantly this swap trims your top-end to lower your curve against a grindy, resource-denial deck built around Wasteland and Urza's Saga. Acererak the Archlich is a clunky 3-mana creature that doesn't help you race their lock pieces like Dark Depths or The Tabernacle at Pendrell Vale, so all four copies come out for a leaner combo-focused configuration. Your Aluren and Show and Tell plans remain the primary way to close games before their land-based engine takes over.