The diagonal that comes with the telescope is a cheap amici. It is common among budget telescopes, but it lowers image quality. It creates a spike in the middle of the image when used with the 26mm eyepiece and increases the blur and lowers the brightness. A star diagonal would be much better, but naturally, it is more expensive.
The red dot finder is as easy as it gets. It is just a red dot on a screen. I would prefer a red dot over any scope type finder since they are easier to align and more reliable.
The 2x Barlow should have been excluded from the package. It is made of plastic, and the lens inside is too small. It can provide a decent image with the 26mm eyepiece, which will provide 46x magnification. But I would use the 9mm eyepiece to get a 67x image instead of using the Barlow.
The focuser is, disappointingly, mostly plastic. I would have expected a metal focuser at this point, but the plastic focuser doesn’t raise any problems in terms of stability and smoothness, so I am willing to give it a pass.