the reach reduction is neat little trick to move the position of the DA trigger rearward.
the 85 trigger is what is in the gun now and with the thin grips you will have the shortest reach possible.
because of the position change, it is not competition legal, but since that is not a concern for you right now. might be a good option.
Plus the other good thing is it's a drop in piece, so like you said, hang onto the factory parts and swap em back if you ever do want to go comp legal. As for the trigger my standard sp01 has the factory recurve assuming like yours. So far forward and I just don't like the feel of the trigger itself. My sp01 tactical has the CGW RRK with the 85c trigger, just a little further back and because of the profile of the trigger you have more surface area across the face of the trigger (granted it's so minuscule) but it does just feel better then the stock recurve. I'm happy as hell with it. Having Stuart put the 85 (old style) trigger on my standard sp01 when I have the money for him to do a production legal job on it.
The straight trigger makes for an easier reach. I'm not sure if it can only be installed on a single action gun.
The straight SA trigger is an option and will obviously move the trigger back, but 1, if its the profile of the recurve sp01 trigger you don't like, even though it's a totally different shape the profile of the SA trigger felt too much like the recurve trigger (to me it did, the flat face and hard edges) , and 2, I think it's a little more work to go back to the original DA versus just removing the reach reduction modified disconnector and reinstalling the stock one (this one I'm not 100% about). I'm pretty sure you can run the factory 85 trigger if you like the feel with your factory disconnector and be competition legal. And 3, it will be SAO if you install it. I personally prefer the DA/SA, but then of course that part is preference.