While alternative forms and layouts were pretty cool and I was a huge fan of PE, I really enjoy the Form Builder now in Kentico v12 and greater. There's a lot of customization you can do to it with a very little amount of code. This post talks about customizing the output of all forms on a site and is for v12 MVC5 but it's very similar for v13 .NET Core. Using the OOTB form widget, custom form sections, custom form controls and customizing the output it's way more powerful than anything we've done in PE. Plus 95% of it is reusable.