Can the motor be modified to improve the power of the Sphero mini?

Hello. I am a Korean university student who is attending hanbat national university in Korea. I am a mechanical engineering student. Currently, I am making a remote-controlled toy top using a sphero mini as my graduation work. The diameter size we want is only the sphero mini, but the power of the sphero mini is insufficient. For the power-up of the sphero mini, please take a look at our ideas and advise if possible and how to get started if possible.

First, disassemble the inside and use a stronger motor. In this case, I am wondering if I need to obtain a motor for myself and write a new coding after installation, or is the company supplying a replacement type power-up motor for training purposes?

The second is to increase the gear ratio and weight. It improves the torque by increasing the gear ratio between the motor and the wheel. Also, to balance, the weight attached to the bottom part is made more heavy. However, if we want to change the gear ratio, the diameter of the gear will change and we will have to redesign the housing. Also, if we change the material of the bottom, it will be difficult to increase the weight as desired.

In summary, the first is motor change, the second is gear ratio change, and the third is weight change.
Is it possible to power up the sphero mini in these ways? If possible, I wonder if the company is supplying related parts. Also, I wonder if there are any educational or experimental materials for students in relation to these power-ups.캡처

This is test gif for toy top’s low part.

As you can see, the moment it is assembled, it does not rotate smoothly. This is the problem we face.KakaoTalk_20200727_165532909