New "Compositional Guides"

For many purposes camera compositional guides in Blender right now are pretty useless and only serve basic functionality, which very often isn't enough. I propose this changes to compositional guides functionality so that they can be as useful as in other softwares. Especially now that 2D is possible with Grease Pencil strong compositional guides is necessary for Blender.

1. Per-camera color and thickness.

Right now only way to change compositional guides color is if you change View Overlay property in the theme -> 3D View. Pretty outdated and bad. Default black is almost invisible unless you have extremely white scene. Moving compositional guides color in the camera data properties would allow you many things:

A) First, easier to change, don't have to go in theme properties.

B) You can't save compositional guides color in blend file unless you change theme, which is very bad idea and you'll have to keep changing theme colors for your every file, when you want to revert back

C) Changing View Overlay color also changes World Origin Point color and is very distracting while working.

D) You'll be able to change it per camera. Lets say for example you have really black scene and you want to change it to red to be able to see it, but in your second camera you have close-up of something red, you'll want to change it to other color for that camera. Super convinient

Changing thickness is also important, as default blender compositional guides are just too damn thin. You need to squint to see them. Having slider that controls thickness would allow us to make them thicker when aligning scene, and make them thinner again when we're done and just want to keep guides.

2. Custom Grid

Below compositional guides presets there should be option "Custom" which lets you insert how many lines you want horizontally and vertically. Preferably other things too, like offset, (curve controls too in perfect world), but basic functionality like in After Effects would be neat.

Currently you can only use Grid to cut your view into equal portions, but only if you're looking down and align camera perfectly. When working with grease pencil scenes it is very important to be able to slice your view in increments to better understand scene and spacing.

3. Show compositional guides in Viewport Render.

Having a button that toggles visibility of compositional guides in render could really help when you want to do test renders to show to others and communicate scene arrangement. Or simply want to do viewport render and show people logic behind your composition.