If it doesn't already exist, I think you just created a product. An easy to remove full laptop sticker that looks like the laptop, and allows you to put on other stickers, then remove the whole thing leaving no traces and protecting from sun bleaching. I bet this is already a thing.
[edit] It somewhat exists. I found "macbook skin's" on amazon.
A good solvent-based adhesive remover should be able to take those marks off. I can recommend De-solv-it "sticky stuff remover" but I have no idea if that's available everywhere. It has a silly name but it works very well.
Anodised aluminium is kinda porous. Penalty some of the solvents have entered the material. Maybe you can get it out with more solvent. Or maybe it'll make it worse...