It can take a lot of time to load Photoshop if you use many plug-ins and they also use memory.
Plug-ins Folder

Now here’s a suggestion; put those plug-ins that you seldom use in a separate directory.
When you load Photoshop hold down Ctrl + Shift (Command + shift on the Mac); a window will pop-up asking you to select an additional plug-ins folder. Select your folder and click OK.

  

  

  

  

  

Photoshop will always use this additional plug-ins folder, until you:

- bring up the additional plug-ins folder window and select Cancel
- change the location of the additional plug-ins folder in the menu; Edit / Preferences / Plug-Ins & Scratch Disks…