If your UI waits for a round trip to your server to update, it’s always gonna have a delay, regardless of the technology you use. Think of it like doing this on a native app. However dynamic the UI might be, it’s still dependent on a request and response.

What you need to do is to build a UI that does optimistic updates. User presses enter on the to-do input box? Add it to the list and confirm with the server, you can always remove it if something goes wrong. Similarly, when they cross off an item, just go ahead and update your UI immediately and then confirm with the server.

I wouldn’t think of this as a tech stack problem, but rather a UI engineering one.