Base Emacs 29 will do a lot for you in those areas, especially with rust-ts-mode (Treesitter powered Rust mode), Markdown mode, Company (a completion tool), and Eglot (lsp server client). I also recommend adding Which-Key to help figure out the bindings in different modes. Built-in eshell is great for scripting / terminal needs.

For a kickstarter config, System Crafters' is pretty nice and will mostly keep you to built ins with good documentation of why they chose things. https://github.com/SystemCrafters/crafted-emacs/ and they have a Rust example config using their modules in their examples.

Doom Emacs and Space Emacs are cool too to show some possibilities and get a full featured ide earlier, but there those setups due add their own learning steps.