By having bents bars on the end of the cells you're not getting as much of the supposed benifit of reduced soldered connections. There's still two just like when using corraly's.

Over here I don't think I've ever seen anyone direct solder, practicly everyone uses corraly tubes. They need a good soldering iron to get them on securely in the first place but once done and with good quality male connectors you're very unlikely to have a disconnection from a crash. As for wiring up the wrong way round, just be clever with your wiring layout, often it's possible to make one wire only long enough to connect to the correct terminal on the battery.