Jetbrains

Key binding

• Use CMD+I to trigger completion

You can assign preferred shortcuts  (Tab and Shift-Tab or whatever keys you like) to Select Next Completion Option and Select Previous Completion Option actions in Settings | Keymap and remove the assignment of Tab to Choose Lookup Item Replace.

Tweaks

• How to stop Escape from Leaving Terminal – IDEs Support (IntelliJ Platform) | JetBrains
• Go to “Settings | Tools | Terminal” and click “Configure terminal keybindings”.
• Find “Plug-ins | Terminal | Switch Focus To Editor” action and change its keyboard shortcut (by default “Escape”) via context menu.
  Keybindings are IDE wide, so no need to change it for each project.