Best tool for smoothing roads?

I am working on creating a hillclimb map based on the recent SCCA "Chasing the Dragon" hillclimb. Everything was going great until I tried to smooth out the road. The only tool I am using right now is the ingame editor and I can't make a road smooth to save my life. Smooth, flatten, and smooth slope all lead to a rough road but a sorta-kinda steady slope. Any ideas what I should do?

Also, I'm 100% new to map design, so any pointers you can give in general would be great.

 

On the top there are strength bars for Pressure, Softness and Height have a play around with those that should hopefully help

 

Ahh, I was wondering what those (specifically pressure) meant, thanks! I will give that a try

Edit: Just wanted to update and say that worked! I clicked on the curve beside softness and pulled everything up to "hard." After this just one trace with flatten followed by another trace with smooth and the roads were near perfect. Thanks again!