These are very nice icons.
However, I see the issue that they expose too many details to be discernible at a size of 16x16. The texts "LPI" and "LPI" cannot be distinguished even on the forum page although they are rendered at 24x24 on a screenshot - but they must work also at 16x16. The paw in the package box looks nice at large magnification, but, again, at 16x16 there is only a black "something" inside the box.
Of course you are welcome to provide images to be used within Lazarus or third-party components when you think some images could be improved (and there are a lot). However, we are rather feature-complete at the moment. There were two authors who contributed to the current icon set, and if you look carefully you can distinguish them. Adding a third author could make things even more nonuniform. But that's just a guess. I just want to say that your drawing style should fit to the other icons (which it seems to do).
Let me give you instructions for the current IDE:
- Since v1.8, the IDE is supporting images at various resolutions on the component palette, and since v2.0 in image lists. Ideally you should provide images at three sizes. The images intended for 96ppi are named simply like before, but image file names for 144 ppi (150%) must have an appended "_150" and images for 192 ppi (200%) must have an appended "_200". See the folder "images" in your lazarus installation as an example.
- ATM the LCL does not support svg images. Nevertheless this may change some time in the future. Therefore, I urge you to provide svg images from which the final png icons can be exported. Note that rendering icons at 16x16 is a challenge. In order to get a crispy 16x16 image you probably must redesign the image for this particular size, so that, for examples, lines do not intersect the integer pixel boundaries and are blurred. See https://sourceforge.net/p/lazarus-ccr/svn/HEAD/tree/image_sources/ for the svg files currently used.
- And the license: Since Lazarus is open source and we distribute the original icons in the installation your license should not be too restrictive.
Looking into the future, maybe we should provide different icon sets. People are always asking for a "dark mode", and I am rather sure that the current icons do not render appropriately on a dark background. Or the current icon style used by many operating systems is that simplistic line-drawn/flat style, the 3-D/artistic/realistic style with lots of gradients is out-of-fashion nowadays. Contributions into this direction would be welcome. But of course, replacing all the icons used by the IDE is a LOT of work. And of course also: nobody is working currently on such a feature, so maybe it is too early to contribute to such a project at the moment.