Yes, but that's not even half of it.

You always want the connection to the servo arm "shorter" and the connection to the surface's horn "longer". And you always want your computer radio to have 100% throw on every servo, no more, no less. That's the most efficient, effective situation for the servo. If the connection on the servo arm is as close in as possible, you'll get whatever power the servo can deliver, and it'll deliver it with the most accuracy. If you have that close connection, the next problem is simply to set the connection on the surface's horn so that full movement of your TX stick gives the recommended surface deflection.

With your existing components you will probably have to swap out that aileron horn to be able to shorten the servo arm connection because that short aileron horn is going TO MOVE THAT AILERON a lot being that short. And if you shorten the servo arm connection, the pushrod movement might not be long enough. There is no rule that says you have to use only the stuff that came in the kit/ARF box.

As you've set up the connections, you're using a fairly weak servo and then putting it at every disadvantage.

If it was my airplane, I'd replace the aileron horns with longer ones. What do they cost? a couple of dollars? Then I'd reconnect the pushrods on the servo arm closer to the servo. Then find out where to make the connection on the aileron horn to get adequate deflection.