Beaver Builder is great. I hope to use it for years to come. Actually they have a plugin, that's for pagebuilding, then a theme, which is perfect for using the plugin on, and a themer that makes the whole package a true theme builder. Before, changing things like the blog layout, the archive layout, the header and the footer, was difficult. It's a breeze now. A joy to work with. Fast, stable, easy.
It is a bit expensive, yes, but I'm glad to pay for it, so that the developers can continue to work on it. I've been using Artisteer, then Headwaythemes, and they are gone now. That's a lot of wasted time on a learning curve for nothing.