UVs to Mesh would be super useful for wrapping new meshes and patterns on an existing object. Often times it is just so much easier to model something on a "flat" plane then morph it back to the original object.
In general two modes of converting UVs to Mesh:
If the object is selected (object selection mode) > convert all UVs to flat mesh. Perhaps additional option to choose UV set if there are multiple sets available on the selected object or convert all sets at once.
Selection based > selected UV shells (one or more) convert to flat mesh, or only selected UV shell from selected UV set only or perhaps you have multi-tile UVs so you can convert everything or just certain tiles and things like that. This one is useful if you have complex UV layout everything all set so converting entire UV layout only makes things complex and tedious to delete or simply gets in a way, especially potentially tiny UV shells converted to mesh. You might need just one part of the mesh so converting only selected UV shells to mesh makes very fast and convenient workflow.
Must have additional options:
1 -- "Integrated" blend shape or morph options between original object and newly created "UV To Mesh" object - as option automatically created on UVs to Mesh conversion and preserves vertex order - very useful so that you don't have to do it all yourself were you need to use blend shape and often time reorder vertices and things like that. I guess in most cases this is the main reason of converting UVs to Mesh so if the tool can do that for you then it would be that much better. Many people might find that manual setup very convoluted workflow and even end up not using the "UV to Mesh" tool because they don't know what exactly to do with it.
This blendshape/morph should be part of the tool itself where for example you have a slider (Envelope?) you just drag from 0 to 1....not creating separate blend shape chain of nodes you have to search to adjust separately and outside of the tool. As i said, this is an option you can choose to create on its creation, if you don't want to automatically create blenadshape within the tool then you can just choose not create it and instead use manual workflow of reordering vertices as you want as well as creating Maya blend shapes, etc.
2 -- Another thing connected to this blendshape workflow would be to either keep original object but create a new object from "UVs to Mesh" command or to create it from existing object (or selection) only. Many tools in Maya have this "keep original" type of option.
3 -- Things to consider is adding an option if you want to automatically slice/detach edges on poly mesh on selected UVs shell borders or selected UVs boundary (depending on which of two modes mentioned on the top you are using). Useful to save additional clicks of manually detaching components yourself so that blendshape/morph can work properly.
4 -- It would be great, if even possible, if you have something similar to "Target Smooth Level" options like what "ShinkWrap" deformer has, which allow you to have lower resolution base object to work with and with that higher performance with blendshape/morph options when you use something like Wrap deformer on converted mesh too instead of applying "Smooth" prior to using Wrap deformer which then makes heavy impact on the performance. Having some kind of an integrated "ShinkWrap" like a smooth level on the base mesh (uv to mesh converted object) might come in very handy and increase performance.
Additional features (if possible) -
-- Linked/instance workflows -- texture painting, edit UVs in 3d space (using polygon tools), editing flat mesh and original mesh receives the changes and the other way around.
Not sure if this one is possible but perhaps it would be handy if you have that option where you can keep modeling in a "flat" layout instead of on complex curvatures of your original model but the original object will receive all the changes done on converted UVs to mesh. Maybe similar workflow can be used in sculpting (using projections, stencil..etc.) where you can sculpt on your converted flat UVs to mesh and the original object receives all the changes. The same if one day you decide to overhaul texture painting so you can keep on painting on the flat mesh and all the changes receive the original object too and things like that.
Example videos:
Attached video I have recorded showcasing current workflow to do the same thing by using a custom script and multiple steps + slow performance, that simply does UV to Mesh conversion and that is it but to make it really useful it would be great to have options mentioned above. Maybe people have other ideas too.
