1. You might not like Samurott, but there's no denying it's attack stats are very high.
2. I was going to suggest Mienshao, but I wasn't sure if you'd want to replace a pure fighting type with another pure fighting type. =)
3. Alright then. =P I would recommend adding an Air Balloon as the item, for fighting in places where there's no chance of losing the item.(Like the battle facilities or wireless battles)
4. Alright then.
5. As a replacement for Simipour; I would recommend training up an Axew into a Haxorus. It might not have a water-type move; but since you say that your bro has an Eelektross; you can use Mold Breaker against him to take the Eelektross down with an Earthquake.

Unless he has a Haxorus already. Then I'm not sure what Mold Breaker you'd want to use.