Are you a native speaker? Because said quickly in typical English it sounds like "wonderfukl" which isn't great.

Not a native English speaker, no.

If OP dropped the g, it would be a MUCh better product name.

Solid advice. Seeing how many here would pronounce it differently, I totally agree hahah

this would make it even closer to the dangerously similar travel planning app "wanderlog"

I actually own wanderfull.ai

Drop an l would be better I think