minor UV efficiency improvement in UDIM workflow

I am super excited about the new UDIM system that's being developed by @lukasstockner97 for blender 2.8. ¡It's going to improve efficiency so much!

So I thought I would share a few tweaks that I think could make the UV work a little more comfortable within the UDIM system.

Disclaimer: In the UV editor, I am not sure what the layout is going to be regarding the new toolbar settings, so I put everything in the current toolbar, as it is in the 2.8 UV editor now. If the toolbar ends up being like in the 3D view, this panel should be in the properties panel instead.

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1: PACKING OPTIONS :

I would personally like to have a whole panel to configure the packing options before the actual packing. In the case of a complex geometry, or multi edit UV workflow, I think it would save time by not having to pack two times (one by default, and a second one after configuring rotation, etc).

Besides that, an option to determine how the paking is going to be distributed across the available multiple tiles would be useful. You could decide:

A) Let Blender decide how many tiles are needed to pack the islands without rescaling them.

B) Manually set a fixed number of tiles for the islands to be distributed.
If free scaling is active, they would be scale to fit within the tiles set. Otherwise, If they don't fit, an error could be prompted, or a warning that would say that they are not going to fit, so you can modify either the number of tiles or the scale of some islands.

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2: EXPOSING COMMON UV TRANSFORM ACTIONS

The * UV vertex * panel in the properties tab is, in my opinion, a panel with wasted potential right now.

In Maya, there is a very useful feature for moving UVs with a fixed manually set number. It allows for something that has been placed and packed within a UV tile to be moved to the same relative place in another tile.

I think It would be very useful to have it there, as well as a couple of common rotation angles and scale ratios (a lot of the time some UV islands you just want to rotate them 90º, and not having to type R,90,Enter each time would be a time saver feature)
There are addons that help the user to do snapping, aligning, rotating, etc, but since the UDIM workflow is new, I believe it would be best to have it as a native option.

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USAGE EXAMPLE

This is how I imagined it could be a workflow of packing within a set of 3 tiles in X, and then moving a couple islands to the same spot in another tile. The example is very simple, but with complex layouts of already packed and manually adjusted islands, it can save time:

It's just a couple of features that I think could be of use in the new workflow, but the best thing would be to implement some of the UV addons features as well, in my view. But since they are already out there, I didn't thought about those features, and how they could be integrated.

Let me know what do yo guys think!