My UI library is designed as a core to build your own UI on top. Perhaps you won’t need to build so many UIs anymore.
I can answer questions if you are suspicious.
In my game, I created this fancy Integer input box built on Apos.Gui: https://gfycat.com/ultimatecomfortablefurseal
I can use backspace and delete to remove characters in front or behind the cursor. I can write integers with any keyboard input layouts. I can use the scrollwheel on my mouse along with up and down arrows on my keyboard to increase or decrease the numbers. I can also use my mouse to move the cursor: https://gfycat.com/smoggycomplexblackrussianterrier
That’s just an example of a custom component.