These spring are all pretty straight-forward. Let's start with the hour-snail detent spring. This should exert enough force to hold the snail in position, with just enough to have the snail rock back when moved a bit away from its rest position. I test it with the snail as shown above - with the longest step horizontal - I push down a little on the long step and see if it will rock back into position when I release.
The strike rack springs provide impetus to move the racks to the left when their respective pawls are lifted. The quarter rack has to move fairly quickly, so its spring tension is typically a bit more than the hour rack - which has lots of time to drop into position. One problem I have found is when the rack springs are long enough that they can press up into the angle between the hub on the rack arm and the small lever arm the spring is meant to press against. If the spring pushes into the angle it can increase the tension on the rack significantly, which can stop a strike train - especially an hour strike train.
The last spring, on the manual release arm - well, it's only job is to keep the lever in is rest position.