The Playstation 4 version that was released this year has the additional skills, 16-bit BGM as well as higher amount of enemies to deal with. There are also special magic spells that cause lots of money or other items, summon various attacks or do the recovery. It surely makes things overall intense with lots of enemies on the battlefield but it can mean the increase of difficulty overall like you're going to have a hard time in higher difficulty even at the highest power. In addition, there are other changes in this version as well such as different announcer, the way the enemy disappears or takes damage and the real fog effects. These changes may be strange to be frank and they still don't increase the Playstation 4 usage level much further and especially for the insane amount of enemies and items on screen which are the only major resource usages of the system. Also, the retroness level is getting that less due to the fog, lighting effects and other effects the retro game systems are not able to handle. Even certain sound effects are not retro at all.
Having to level up and unlock skills is a tedious task and that concept to me should not be in the game. Also, another strange thing is that other characters are completely powerless that they are seriously weak in the first place and the worse thing about Arcade Mode is that there's no way you can strengthen the characters after every stage. Lastly, the Playstation 4 version worsens things a little bit with the decrease of retroness level by adding real fog and lighting effects which are way beyond many retro game systems can do.
These enhancements mentioned above can also be in other versions of the game as well but I don't think that will happen at anytime.
