Update CONTRIBUTING and issue template(s) for feature requests

.github/CONTRIBUTING.md

@@ -4,7 +4,7 @@
 
 Note that bug reports and feature requests for related projects should be filed in the corresponding repositories for [i3status](https://github.com/i3/i3status) and [i3lock](https://github.com/i3/i3lock).
 
-## i3 bug reports and feature requests
+## i3 bug reports
 
 1. Read the [debugging instructions](https://i3wm.org/docs/debugging.html).
 2. Make sure you include a link to your logfile in your report (section 3).
@@ -18,6 +18,20 @@ Note that bug reports and feature requests for related projects should be filed
    encountered the issue you are about to report while using a compositor,
    please try reproducing it without a compositor.
 
+## i3 feature requests
+
+1. Read the [project goals](https://i3wm.org) on the website and make sure that
+   they are compatible with the feature you want to suggest.
+2. We are generally happy with the current feature set of i3 and instead focus
+   on maintenance such as stability and fixing bugs. New features will rarely
+   be considered if they require additional configuration and/or commands, or
+   if they add significant complexity (either through the exposed configuration
+   or mental complexity) to the project.
+3. Explain in detail what problem the feature addresses and why existing
+   features fall short.
+4. Consider whether the feature could instead be implemented using the
+   [IPC](https://i3wm.org/docs/ipc.html) or other external tooling.
+
 ## Pull requests
 
 * Before sending a pull request for new features, please check with us that the

.github/ISSUE_TEMPLATE.md

@@ -3,7 +3,12 @@ PLEASE HELP US PROCESS GITHUB ISSUES FASTER BY PROVIDING THE FOLLOWING INFORMATI
 -->
 
 ## I'm submitting a…
-<!-- Please check one of the following options with "x" -->
+<!-- 
+Check one of the following options with "x".
+
+Please note that at this point we focus on maintaining i3 and fixing bugs, and will rarely consider features which require further configuration or significant complexity.
+In such cases you should consider and present specific benefits derived from adding this feature such that it can be weighed against the cost of additional complexity and maintenance.
+-->
 <pre>
 [ ] Bug
 [ ] Feature Request

.github/ISSUE_TEMPLATE/feature_request.md

@@ -8,7 +8,7 @@ PLEASE HELP US PROCESS GITHUB ISSUES FASTER BY PROVIDING THE FOLLOWING INFORMATI
 -->
 
 ## I'm submitting a…
-<!-- Please check one of the following options with "x" -->
+<!-- Check one of the following options with "x" -->
 <pre>
 [ ] Bug
 [x] Feature Request
@@ -28,6 +28,15 @@ Describe the desired behavior you expect after mitigation of the issue,
 e.g., »The window left next to the current window should be focused.«
 -->
 
+## Impact
+<!--
+Please note that at this point we focus on maintaining i3 and fixing bugs, and will rarely consider features which require further configuration or significant complexity.
+In such cases you should consider and present specific benefits derived from adding this feature such that it can be weighed against the cost of additional complexity and maintenance.
+-->
+<pre>
+[ ] This feature requires new configuration and/or commands
+</pre>
+
 ## Environment
 <!--
 Please include your exact i3 version.