In learning a throw, once you can achieve a recognizable effect that you can identify as that particular technique...
There is a tendency to add more power in order to try to make more amplitude or a harder landing or in order to accelerate the take-off. But often the added power spoils the effect. So, what to do? Once you can make a throw go pretty good, how do you improve it?
Hint: this is Ju-do. (even if you happen to be calling it aikido, it's still ju-do.) Try this:
Once you can achieve an effect that is recognisable as a certain throw, try reducing the power until you cannot make the throw work anymore. Then increase the power until you can make the throw again. In this way, you can find the minimum power that you have to have to make the throw work.
You want to practice in and around this minimum-power level. Over time, as you get better, you will find that what you thought was minimum power is too much power and you will be able to reduce power again. Resist the urge to add power for more effect - instead, reduce power while trying to get the same effect!
If this sort of practice makes you feel like you are doing wimpy-jutsu, then instead of thinking about it as throwing with minimum power, think about it as holding more and more of your power in reserve in case of an emergency - as developing a bigger and bigger hammer to drop on the opponent when your low-power throw does not work. :-)