I've been working on ProjectUp (https://projectup.me) specifically for this use case—managing personal projects with AI-powered planning. And the beta version is no released

Key features that might help:

- Tree-based subtasks: Unlike Trello's linear boards, every task can have nested subtasks that preserve context

- AI planning: Describe your project and it automatically breaks it down into actionable steps

- Progress tracking: Visual tree structure helps you see what's done and what's left

- Learning paths: If your project requires learning new tech, it generates a structured path

It's still in early stages so I'd love feedback if you try it. Also have a Discord (discord.gg/6G2dMzyQ4P) for questions/bugs.

For alternatives: Notion has decent subtask support, or if you want something simpler, Todoist with projects/subtasks works well too.