The only reason to have a centerstand on the bike is to do maintenance when the bike is on a level, solid surface such as a garage floor. The bike is much more stable for general parking when the side stand is being used. A simple test would be to try to tip the bike over in both scenarios. You will find it is much easier to push the bike over when on it's center stand. Always try this test with an assistant.
As for the side stand sinking into hot pavement more than a centerstand, well, as Rhino says, put something with a larger footprint under it, even a crushed beer can will do. If you don't, the bike will sink into the pavement, but probably won't tip over. My C14 has been leaned over quite a bit, but still "upright" when I've forgotten to put something under the pad. In the same scenario, with the centerstand, the side in the sunlight will sink in, while the other side will not, resulting in a tipped over bike.
The sidestand is not fragile. The weight of the bike is no where near what it would take to fail the sidestand in a compression failure. The steel in the side stand is incredibly strong, especially in a compressed mode. When my girlfriend and I go riding I put the bike on the sidestand for mounting and dismounting. She gets on, then I get on, all with the bike on the sidestand and with all of our gear on the bike. Probably an extra 500 lbs. No problem.
Finally, there is no reason to take load off the springs. They are made to withstand much higher forces than the weight of the bike and will never fail for that reason.
Just my opinion, let's hear others.
