A text editor based on markdown may not meet your needs then. It’s not a word processor / desktop publishing app. People often choose markdown editors because they don’t want fine-grained formatting tools to fiddle with. It can distract from getting work done. It’s not a problem with Obsidian. All markdown editors I’ve used are built this way. It’s a deliberate, opinionated design decision that doesn’t suit all people and all workflows.
As a researcher and writer myself, I can understand your desire to use Obsidian’s other features for your work. This may be a case, however, where your formatting workflow needs to adapt to the tool and not the other way around. That said, one of Obsidian’s strengths is its customizability. Could you describe more specifically how you’re using different text sizes in your writing workflow? Maybe show an example or screenshot? This community is very helpful and may help you find an adaptation. Someone may even build you a custom CSS snippet that will get you most or all of the way there.
Personally, I use headers and highlights to make certain lines visually stand out in a note. I customized my CSS theme to set the colors and sizes I like. Sure it may look a little unconventional, and introduces extra line breaks to use headers, but they fulfill the function well. These notes are for me and my understanding. No one else is going to see them. If I prepare something for sharing and publication, I’d copy the text into a different app, one designed for formatting and presentation.
