There is *some* overhead for each tiddler definition, but it's not really all that much.
Here's an example of the HTML file content for an empty tiddler named "New Tiddler":
<div created="20200607084511503" modified="20200607084514434" tags="" title="New Tiddler">
<pre></pre>
</div>
As you can see, excluding the actual title text (New Tiddler), the overhead is just 87 bytes per tiddler.
Thus, the overhead for 1024 separate tiddlers would only be around 87K. Considering that an empty
TiddlyWiki (with just the default TWCore, no plugins and no other content) is about 2.2Mb, the
overhead for creating separate tiddlers is generally insignificant compared with the total filesize.
enjoy,
-e