VS 0-200fpm is a Boeing procedure, most company use it, my company uses VS 200, some do VS 0. The 3. segment allows a level off. Airbus SOP do the same, push to level off (VS 0) to accelerate.
I think using VS is the easiest way to do this. What would be the advantage using a SPD mode? Doesn't it still climb that way?
And yes we do use Flap 15 on G/S with gear up, sometimes even Flap 20.