My first time looking into this thread, very nice updates on the build process and the pictures were great.
Not exactly "looking forward" to the first time I have to rebuild my engine, but on the other hand it does look like it can be fun, minus all the unplanned hassles.
As far as your question about tires, I honestly don't think you can have both ends of the spectrum. If you want awesome dry traction, you're going to have to be careful in the rain. If you want tires that can handle rainy roads, you may have to sacrifice dry launch traction.