Okay good, I thought I was the only one who had trouble lol. Yeah I was a little too aggressive and rushed a lot but I'll change my play style on SS. I should be able to grab the last couple attachments on SS hopefully, because I have no idea what some of the under-barrel attachments were (bayonet, I assume). Thankfully I was able to find and unlock all the nanosuit modules Now it's just a matter of grinding out their requirements!
Nah I had trouble on Recruit too but obviously that's because I was rushing/guns blazing as I suspect you were too. You can cloack the whole game just like on the first two games which makes SS a breeze. Don't forget to make your backup saves just incase.
Don't worry about the weapon attachments I was only missing 2 by the end of my first playthrough and they were the two suggested on the forums. It's the glitched nano kits you should be worried about.