So I just finished playing SA X Ep. 2 a couple of days ago and did so after having played part 1 months ago.
I found SA X Ep. 2 to clearly be bigger than it's predecessor and what made it so fun for me was the story. You did a good job on letting various characters interact with one another in a believable fashion.
What also was fun was beating up all those Foot Clan Soldiers but I must admit that it got pretty tedious for me in the 3rd and final chapter. After 4 screens or so I thought to myself "man just stop spawning enemies that prove no challenge to beat and give me the boss already".
Speaking of the boss, while I do like the fact you made that episode's final boss battle with the Shredder a two-phased fight, I felt like the helicopter battle was too easy, which combined with the fact that it's health bar went down so slowly no matter how many rapid fire gunshots you fired at it, made the whole battle feel like it got dragged out longer than it had to be.
Finally I did attempt to get those A ranks but I can't believe how you expect people to get those ranks if you're not even telling them what your rank is based on.
I know it is calculated by two factors, "Enemies" and "Performance" multiplied by a certain number but here's the thing :
What is the Enemies score even based on? The amount of enemies you defeat yourself (not counting the ones your partner defeats)?
What is Performance based on? Solely on how much damage you take over the level? Is it based on how much you correctly time your blocks?
And finally the multiplier, how is it determined by how much your combined enemies and performance score is multiplied? I had x2 and x3 so far but I really didn't know how I got those.
Honestly I think this whole ranking system should have been explained in your Author's comments. I know barely any people have gotten those A ranks but knowing that nowhere in the game or by you the ranking system is explained in detail, I understand why that is.
But overall you've got something good in the works. If what I said can be kept in mind for SA X Ep. 3 and if the ranking system could be explained for episode 2, then that would make something which is already good, great.
EDIT : Thanks for explaining the ranking system, I'll get back ASAP to this game now to get all the A-ranks and their associated medals.