Atra du evarinya ono varda.
Any suggestions for the final member?
I suggest a Dragonite, evolved from the special Dratini the guy in the Dragon's Den gives you if you answer the questions correctly. A dragon-type is always a good member in any party.
If you want, it comes with a moveset of my choice:
Dragon Claw/Outrage - powerful STAB
Earthquake - to deal with Steel-types
ExtremeSpeed/Waterfall - comes with the special Dratini's initial moveset & priority move/for type coverage
Swords Dance/Fly - Attack raiser/STAB
Hope this helps. If there's anything else, feel free to ask me/anyone. :)