JMO but the software seems limited, but at the price you can't expect all the bells and whistles. It builds 4 or 5 "silos" max which goes 3 levels deep max. I was trying to add more from the Wordpress dashboard and was surprised to find that it created posts. Wordpress creates a dropdown menu from child PAGES in the same way. Thus I couldn't find a way to "extend the silo".
Also posts that are added after the site is created will end up bumping the Weblyfy homepage down unless you make it a sticky or the homepage. The links in the sidebar and tags also seem a little funny. Try "Googling" silo structure and view the images and you'll see what I mean. You could manually remove the sidebar widget, and be careful when adding tags, but JMO I think I'd rather have pages instead of posts, especially with a site that's more of a set and forget. Pages with the "child pages are more "siloed" IMO (that's just me )
That being said I'll try some manual tweaking and try it on some less competitive keywords in the non-IM niche.