Everything will be built to code but you might want to see what insulation they put in, getting it upgraded now can save in the long run.
Each builder is different but paint is paint. See if they will do two tone or different colors in different rooms if you want something other than white.
Make sure grading is included around the house and you aren't left with a mess
See if AC is included.
See if you can pick the front door out
What type of windows are included. Now is the time to upgrade is you want something better or more efficient