-First question, I recently stumbled on a way to create a custom JPanel(image) and custom JButtons(own images) and paint them to a JFrame which holds a  game board for painting 2dgraphics. Is this an ok way to have a UI the custom JPanel with my Custom Buttons on it?
-Second Question, what is the basic concept for character customization for sprites etc, like a basic image for a player and then being able to eqip armors and stuff, what is the logic etc behind doing so?

Thanks in advance =D.

What I mean is that, is this an acceptable way to make a UI, atm I pretty much I have  a frame which has a Panel which holds buttons which open up different menus"character screen, abilities, settings" instead of me drawing a rectangle I just used a JPanel on the bottom of the screen that Is static and whenever I add a game Panel eg board it gets painted with it.