Can’t say how hard it is to remove the rear shocks. I have an si and my installer just had to remove a 17mm and 19mm bolt, pull the rear spring out and slap the new one in without having to trim the bump stop. My guess is you have to go into the trunk, remove some of the carpet covering the rear...
Spring rate on the Swift's are probably going to be higher as usual. Eibach will be softer if you prefer are more tame ride OEM+ like ride. Regardless, the thing making the FL5 too harsh, even on comfort, is the dampening, not the actual spring itself. Big reason why a lot of people are buying...
Basemap.
Throttle padding is all up to how you drive. Some people like soft others like the middle option and I forgot what the most aggressive one was called. You can always do soft and it’ll be closest to stock.
Well, the tune will turn up the boost a bit more so you’ll notice much more torque in the midrange and a bit more top end. You can get a faster turbo spool and change the rev hang to have less or none at all. There’s a few other parameters you can change but with less rev hang and just the 18psi...
lol every time I bring up how much the better it handles than the previous si I get laughed at. Everyone is so focused on the numbers the car makes versus the chassis/suspension changes. Even the stock tune as you said mimics an NA car so it wants to be revved out instead of dying after ~5500rpm...