The WL will only tell you the ratio about the force (your weight) applied to each square feet of your wing.The glide ratio and airspeed is influenced by the canopy size, the canopy shape, number of cells, material, the trim, and other variables and they are not a fixed number, it's dynamic according to the inputs given to the wing. If you think a high performance wing, it can have a lower glide ratio with the commands released on a level flight, if compared with a student wing, but it's also much faster and it can "store" much more potential energy, so you have a longer recovery arch ending on a infinite glide ratio (horizontal flight) for a certain amount of time (it's how you do swooping), something not attainable with a student wing.
To resume (there's many other variable, this following is simplified):
- Same wing, increased WL (if you compare two jumpers with different weight under the same wing, or if you put some lead on you): the glide ratio will not change, but the speed will do; ie: you can have a more powerful flare.
- Smaller wing, same WL (you scale down the wing but so the jumper weight): the glide ratio will decrease, the speed will increase: same consequences as before, but amplified;
- Smaller wing, increased WL (you scale the wing, but increasing the WL; ie: using a smaller wing than before, or adding weight on you): the glide ratio will decrease even more and so the speed (will increase): again, decreased glide ratio with no commands, much faster speed, much more energy to use during the flare... so you end doing those swoooops.