That used to be me. Can I suggest you check out Dynalist? It's actually maintained and updated (unlike Workflowy at this point), with more useful features. I've been finding the colouring, headers and bookmarks very useful.
Two things I dislike though, 1) as far as I can tell the dates/times can't trigger notifications. 2) the paid plan is expensive.. they give so much away for free, but then charge a lot for seemingly little. A $3/m tier is a good price point imo for a todo app. Right now it costs basically the same as Netflix..
https://dynalist.io/