From my own experience ,my first planes i bult 20 years ago when starting in RC ,were balanced level as that was what i did flying control line for 5 years
My planes would not come down to the runway on final
You must have a --slight bit of nose down , built into the CG or the plane will just hang in the air ,when you need it to decend and touch down
Level makes the plane to floaty over the runway
Bin there done that !