Geometry Nodes becoming a complete geometry modifier builder

Blender's geometry nodes system is powerful, but lacks a few important features:

1. Existing modifiers cannot be applied inside of geometry nodes (bevel, skin etc. which could be added as nodes to allow for completely procedural models)

2. A way to show different inputs in group input conditionally for a better user experience, and have different tabs in a geo-nodes modifier, like the inbuilt Decimate modifier, which has various tabs, options grayed out when checkboxes aren't checked, etc.