The Fate of The Big Rat...

So, I captured the big rat and removed his mask, but I’m at a genuine loss for what to do. I don’t feel like turning the thing in to the authorities, and it seems that killing him and keeping him alive give you the same reward, but releasing him will take away all of you &quotconcerned about ratly matters&quot quality.
If I keep him alive, is there anything that will involve him in the future? Or will this be the end of his mentions?

You get this permanent storylet in your lodging if you let him go but I don’t think there is anything else that changes

He can be useful for grinding Casing and Running Battle, if the need arises.

I have a similar question, but what about the Albino rat which requires to kill him or hand him to the constables? From what I see on the wiki, it offers some help in the Iron Republic.
As it’s more relevant here, can someone PM with the Fate-locked options regarding the Albino rat? Any extra piece of information would be appreciated!
EDIT: Regarding the Fate options I am not talking about the one that resets your Big rat battle nor the one that, most certain, gets your disgraced rat back. I’m interesting in Stealth Watch Repair card and any other options that may use the white rat. :D
edited by Skinnyman on 6/13/2016

He is also pretty much the only reliable source for Dark Dewed Cherries.

Capering Relicker -> ‘A droll pastime’ is a recurring way to obtain it. 60% chance, and the opportunity card shows up often enough over time that you probably won’t feel a need to go out of your way to farm cherries.
Or, at least, the 101 cherries that I currently have aren’t going to vanish anytime soon. :-)