Refine docs.

doc/src/start/builds/minimal.md

@@ -17,6 +17,16 @@ opt-level = "z"     # optimize for size
 ```
 
 
+Use `i32` Only
+--------------
+
+For embedded systems that must optimize for code size, the architecture is commonly 32-bit.
+Use [`only_i32`] to prune away large sections of code implementing functions for other numeric types
+(including `i64`).
+
+If, for some reason, 64-bit long integers must be supported, use [`only_i64`] instead of [`only_i32`].
+
+
 Opt-Out of Features
 ------------------
 
@@ -28,13 +38,17 @@ Omitting arrays ([`no_index`]) yields the most code-size savings, followed by fl
 ([`no_float`]), checked arithmetic/script resource limits ([`unchecked`]) and finally object maps and custom types ([`no_object`]).
 
 Where the usage scenario does not call for loading externally-defined modules, use [`no_module`] to save some bytes.
-Disable script-defined functions ([`no_function`]) only when the feature is not needed because code size savings is minimal.
+Disable script-defined functions ([`no_function`]) when the feature is not needed.
+Both of these have little code size savings.
 
 
 Use a Raw [`Engine`]
 -------------------
 
 [`Engine::new_raw`](#raw-engine) creates a _raw_ engine.
-A _raw_ engine supports, out of the box, only a very [restricted set](#built-in-operators) of basic arithmetic and logical operators.
+A _raw_ engine supports, out of the box, only a very [restricted set]({{rootUrl}}/engine/raw.md#built-in-operators)
+of basic arithmetic and logical operators.
+
 Selectively include other necessary functionalities by loading specific [packages] to minimize the footprint.
+
 Packages are sharable (even across threads via the [`sync`] feature), so they only have to be created once.