Maybe you don't really need to do soldering to change the switches. It is possible to open an ALPS switch without desoldering it from PCB board. From my observation it seems all the clicky or tactile feeling is due to the click leaf and the contact leaf doesn't seem to have much effect on this. (I only observed Matias clicky switch and quiet switch. Their contact leaf seems identical to me). I have a keyboard with Matias quiet switch and one day one key feel kind of weird. So I just open that switch and swap its click leaf, spring and stem with a spare switch, leaving its original contact leaf in place, which is soldered on the PCB. After swapping, the key feels normal again.