Smart Loops Toolkit is a set of modeling tools for Blender that work on your mesh geometry inside edit mode. It can upscale the resolution of geometry in seconds, including boolean cutouts, without distorting the surrounding faces, and it lets you undo and redo bevels.
The toolkit includes a Subdivide Loops tool, an Unsubdivide Loops tool, a Fix ngons tool, a Recalculate loop tool, Straighten loops and Straighten faces tools, Unbevel and Rebevel tools, and an Align view tool. The Subdivide Loops tool offers a closed curve option and selectable curve types, while the Unbevel and Rebevel tools include a precision parameter for handling inaccuracies on flat surfaces.
All of the tools can be reached from the N-Panel under the Edit tab or through the right mouse button in edit mode. Smart Loops Toolkit supports Blender 3.0 through 4.5, is distributed under the GPL license, and has a Discord community for updates, help and bug reports.