Is there any plans to make QMC2 a little more visual? I mean, such as LaunchBox, where you can see the games list as icons instead of text only (icons of arcade flyers for arcade games or game boxes for consoles/computers). Their visuals are very impressive but it is a paid frontend

Isn't it possible to do that as a skin in QMC2 Arcade?

I tried QMC2 Arcade but none of the functionalities/settings menus of the main QMC2 seems to be available at that mode. It is meant to run on an Arcade machine with limited controls I guess.

Well, yes, QMC2 Arcade's functionality is somewhat limited compared to the main GUI. It's actually a wanted design concept... but RB is right, it's mostly a question of "themes", and the Qt / C++ back-end needs to support some of the features as well. There are currently two themes: "ToxicWaste" and "darkone". ToxicWaste supports icons (displayed as part of the item-delegates in the machine-list), but you probably mean something else?!