[support] Another Drupal vs WordPress question

[Drupal]

Hi to all,
Actually, I'm not asking which CMS is better or something. I use Drupal for almost 6 years but, still, I would put myself to "higher beginner" level. 90% of my websites are small, simple, intro websites I built for friends and "clients". Mostly with News, Basic, Events/Calendar, Webform, Forum... content types. Pretty standard. 
So, my question is "When is Drupal to big for a website?" When would WP fit better? Or even when would home-made-code fit better? Where is "the line" you step over and have to use Drupal? If a small nonprofit asks you to build small website with some basic stuff, for free if possible, would you still build it on Drupal?

Thanks for any input,
afan