OK, since this is now relevant, let me try again with the magic. Again, I am intentionally restricting it to just four items so I am being consistent with the form of the published abilities..
Mask: You may change the appearance, to any degree, of any one person or object, and it will appear as that object to anyone observing it. If the disguised thing or person moves or speaks, roll at Advantage to avoid suspicion. If failed, someone will know something is wrong, but might not know exactly what or figure it out immediately.
Invisibility: You may make yourself or any one person or a single object human sized or smaller invisible. Anyone trying to find them is at disadvantage. All attacks on an invisible target are at disadvantage. If you or someone is invisible, they can make their first attack at advantage, but the invisibility is then broken.
Projection: You may create an image of anything with a volume of 1000 cubic feet (10x10x10) or less. It can move, make sound, and have smell. It may simulate a living creature, or an inanimate object. Anything within the image cannot be seen, but anything so concealed cannot leave the boundary of the image or it will ruin the effect.
Phantasm: You force the target to make a Save Test. If failed, the target thinks you are the most terrifying thing they have ever seen or heard. They are at disadvantage for all actions until they make a successful save test.
More explanation for the items above to help set parameters of what I am thinking ...
Mask is just Disguise Self. It basically puts an illusion around you, but you are still you. So, if Skeeve casts it on himself to look like an ogre, he looks like a full sized ogre, but he is actually still only his normal size and doesn't actually fill the entire volume of what the ogre takes up. He is also still Skeeve strength and does not have ogre strength. If Skeeve makes himself look like a duende, he looks as small as a duende, but, while everything bigger than the duende shape is effectively invisible, it is still there. So, if he has to go through a duende sized door, he will have to bend over, meaning his duende image will have to bend over, making things awkward.
Invisibility is just standard Invisibility and the mechanics use the typically TD implementation. It applies to one person or object and lasts until the invisible person attacks, or the caster dispels it, or the encounter ends. I figure the caster can only have one such effect going at a time.
Projection combines your Veil and Cloak and my Image. The idea is that it can make any kind of image. So, it can be a threatening creature that looks, sounds, and smells real (but is completely insubstantial), or it can be a stationary thing (like a big rock or a hut or a bonfire). If there is anything inside the bounds of the image, they are completely hidden. Not invisible; just hidden. So, if the image is a big rock, then anyone or anything "inside" the rock cannot be seen. Likewise, anyone behind the image cannot be seen. If that boundary is breached, the illusion is ruined. They don't have to be completely still, just "stay within the lines". Obviously, this will be very difficult if the image moves, and will be much easier if the image is static.
This is not really a group invisibility spell, due to the need to stay within the bounds of the illusion. (Or stay on the opposite side of the illusion.)
Phantasm is basically the same, but the roll is now a target's save test rather than an attack roll. (I can go either way. Whichever you think best.)
Does this revision work better?