docs: Add copywriting and design tweaks (#17514)

Follow up to https://github.com/zed-industries/zed/pull/17505. This one
contains a bit more copywriting adjustments. Figured we were using the
"You can do x..." sentence shape quite frequently, so tried to kickstart
reducing that slightly. There are also more images not loading in
complement to the one I removed, but I'm not fully sure why that's the
case.

--- 

Release Notes:

- N/A

docs/src/themes.md

@@ -4,11 +4,15 @@ Zed comes with a number of built-in themes, with more themes available as extens
 
 ## Selecting a Theme
 
-You can see what these are installed and preview them from the Theme Selector. You can open the Theme Selector from the command palette with "theme selector: Toggle" (bound to `cmd-k cmd-t` on macOS and `ctrl-k ctrl-t` on Linux). Selecting a theme by moving up and down will change the theme in real time and hitting enter will save it to your settings file.
+See what themes are installed and preview them via the Theme Selector, which you can open from the command palette with "theme selector: Toggle" (bound to `cmd-k cmd-t` on macOS and `ctrl-k ctrl-t` on Linux).
+
+Navigating through the theme list by moving up and down will change the theme in real time and hitting enter will save it to your settings file.
 
 ## Installing more Themes
 
-More themes are available from the Extensions page. You can open the Extensions page from the command palette with "zed: Extensions". Many popular themes have been ported to Zed, and if you're struggling to choose one, there's a third-party gallery hosted by https://zed-themes.com with visible previews for many of them.
+More themes are available from the Extensions page, which you can access via the command palette with "zed: Extensions" or the [Zed website](https://zed.dev/extensions).
+
+Many popular themes have been ported to Zed, and if you're struggling to choose one, visit [zed-themes.com](https://zed-themes.com), a third-party gallery with visible previews for many of them.
 
 ## Configuring a Theme
 
@@ -28,9 +32,9 @@ By default, Zed maintains two themes: one for light mode and one for dark mode.
 
 ## Theme Overrides
 
-You can also override specific attributes of a theme, by using the `experimental.theme_overrides` setting.
+To override specific attributes of a theme, use the `experimental.theme_overrides` setting.
 
-For example, to override the background color of the editor and the font style of comments, you can add the following to your `settings.json` file:
+For example, to override the background color of the editor and the font style of comments, add the following to your `settings.json` file:
 
 ```json
 {
@@ -45,17 +49,15 @@ For example, to override the background color of the editor and the font style o
 }
 ```
 
-You can see which attributes are available to override by looking at the JSON format of your theme. For example, [here is the JSON format for the `One` themes](https://github.com/zed-industries/zed/blob/main/assets/themes/one/one.json).
+See which attributes are available to override by looking at the JSON format of your theme. For example, [here is the JSON format for the `One` themes](https://github.com/zed-industries/zed/blob/main/assets/themes/one/one.json).
 
 ## Local Themes
 
-You can store new themes locally, by placing them in the `~/.config/zed/themes` directory.
+Store new themes locally by placing them in the `~/.config/zed/themes` directory.
 
-For example, to create a new theme called `my-cool-theme`, you can create a file called `my-cool-theme.json` in that directory.
+For example, to create a new theme called `my-cool-theme`, create a file called `my-cool-theme.json` in that directory. It will be available in the theme selector the next time Zed loads.
 
-It will be available in the theme selector the next time Zed loads.
-
-You can find a lot of themes at [zed-themes.com](https://zed-themes.com).
+Find more themes at [zed-themes.com](https://zed-themes.com).
 
 ## Theme Development