The original Exile was pretty easy once you learned the game. Exile II was hard but for the wrong reasons. Once you learned the flaws though, you could easily learn ways to exploit them and the game ended up being almost as easy as the first. Most people never made it past Djinn though, I can't tell you how many emails I've gotten from frustrated players wanting to know how to beat that a$$hole. I always thought Djinn should be the final boss, because the real final boss of the game was a pathetic joke, even compared to the creampuff final boss of the original Exile. And the Japanese version is even easier.
The sad part is that Exile II, due to its glitches, flaws, and annoyances (such as the ultra-annoying dialogue sound effect!), has little replay value whereas the original Exile has plenty of replay value despite being easier and a little shorter.
Cadash? Relatively easy, depending on who you play as and your knowledge of enemy patterns and level makeup. I found the Ninja, despite having low attack power at the beginning, to be the most powerful character once you make it into the second world and ESPECIALLY after obtaining the Dagger Of Swallow. Now there's a game again with plenty of replay value, I must have played all three versions (Arcade, TG, and Genesis) hundreds of times over.