I'm just a beginner at this, but based on my meager experience, the higher the wing loading, the faster it has to fly to develop enough lift to fly.  I have been told by Pat Tritle (RC plane designer) that, "Light is Right".  The lighter the plane, the slower it can go, and the easier it flies.<div>
</div><div>BUT...lightweight park fliers won't tolerate a lot of wind.  I live in a very windy area, so I have better luck with moderate wing loading and stronger motors to better be able to penetrate the wind.</div><div>
</div><div>It seems to me that most of the foamy ARFs, which are great trainers because they can be so tough, are also moderately heavy, with 22 to 24 ounces pretty typical.  My first real successful trainer, the Multiplex Easy Star, weighed in about 24 oz and only had a brushed Speed 400, barely powerful enough to EVENTUALLY get up to altitude, but can't handle more than about 10 mph breezes.  </div><div>
</div><div>Maybe I'm rambling a little bit.  I am just barely a novice at flying, and just sharing what little I know.</div>