I have never had to hold up elevator on my warbirds when taking off.  Seems like a recipe for disaster as you might get airborne and then hit stall speed.  If balanced correctly my planes tails leave the ground at speed and run on the mains.  A little up sporatically might be needed to prevent nosing over on grass but ive never had to hold positive up till I reach flying speed.   As for steering when your are accellerating down the runway, rudder controls the tracking.  slow enough to have the tial wheel down or fast to the point the plane is only riding on the mains.  Ruddder rudder rudder.   I have also found that accelerating too slowly makes tracking hard.  What works for me is a brisk throttle advance to about half throttle and then to full.  Not accellerating so fast that you cant correct in time with rudder but no so slow that ground handling is a difficult.