With the correct servo arm lengths, you should not need the saver on the throttle at all. If the servo binds at one end, then make some adjustment to pushrod length. If that doesn't eliminate the binding, then use a different servo arm hole to reduce the throttle arm travel. Should be just fine!

For the nosewheel steering, I wouldn't use one there, either, unless you're concerned that you're going to be doing a lot of very hard landings or ripping out the nosegear. Even then, if you hit hard enough to rip out the nosegear, the saver isn't going to have enough travel to make much difference.

...my opinion.