Blender gets slow due to Bone use and Mesh scale

Thanks to the Blender developers,
Hello, I love Blender so I use the Blender in my office. But I am facing 2 problems with the use of the Blender. 1) Blender gets slow If I use more bone to rig. The more bones the more get slow. It takes 4 to 6 seconds to select a single bone during the rig. If I reboot the Blender it gets fast for few minutes and then gets slow again. I
cannot use the rigify rig because of the slow issue.
2) If I scale mesh the Blender gets slow gradually. Besides, Where I can use 3 or 5 lakh vertexes and can operate smoothly in Maya but Blender gets very slow to operate smoothly. Why does this happen? I have used in Maya but Maya doesn’t get slow due to these issues. Is there any solution to solve this issue?

I hope Blender developers solve these issues very soon.