Need New Team Ideas

I've played through pokemon Black / White 2 so many times, and I'm running out of team ideas. You can only bare evolving Riolu into Lucario with 220 happiness so many times... I'd like to keep the starter pokemon, and I don't want to use any legendaries because it never feels like I really defeat the Champion with a Cobalion on my team.

Samurott - Use him for your HMs, he has good stats so if you considering HMs to be weak attacks, he will definitely be able to handle them well.
Crobat - Has useful poison moves and is of course a flying type. Since flying types have several advantages against Bug, Fight... they can definitely be used well.
Magnezone - Strong Pokémon, he and Electivired are for me the strongest non-legendary Electric types.
Camerupt - Earth and Fire? Think about the type advantages mate!
Roserade - Grass and status effects right?
Umbreon - If you hate the overpowered Psychic type and are scared of Ghost Pokémon, use Umbreon!

I don't have a clear view about their movesets, that is something you will have to find out. Learn Crobat Toxic and make sure Roserade can paralyze your opponents. This team could be very useful. You will have to do some research on how you can obtain them, they are all obtainable. Magneton evolves by leveling in chargestone cave, Golbat by friendship and Umbreon is a bit of a guess.

In my last playthrough of White 2, I used Azumarill, Weezing and Galvantula with good success.

Just get an Azurill with Hugh Power at the beginning and teach it Work Up and Return (both available right after the first Badge). Later on it also gets access to Waterfall and Ice Punch (although, for the latter you need to farm some shards).

Weezing has a nice defense and can help Azurill to set up at the beginning with some Smoke Screen support while later on still being useful with its decent special attack and moves like Flamethrower and Sludge Bomb.

Galvantula is just your usual fast hard hitting mon, that can make easy use of Thunder, thanks to its ability Compound Eyes.