Scrafty is a pretty good Pokémon, I feel; yours has got Moxie ability, so every time you take one of your opponent's team members down with, its Attack stat would be raised immediately, making it even easier for you to defeating opposing Pokémon. As far as moveset goes, it's very solid. If I were to have Scrafty on my team, this is what I'd likely use.
Though, if you're planning to have Krookodile on your party, you'd like want to have it take Scrafty's spot, as they're more or less equal. Just like Scrafty, Krookodile could have Moxie, I believe--does yours carry it?--and it also has access to a variety of moves which you could find helpful, such as Crunch and Earthquake. I'd recommend you to give it a go and see how things are; if Krookodile works for you, that's great! If not, you are always free to revert to Scrafty.
If you wish to put Roserade onto your team as well, I'd suggest replacing Cohagrigus, perhaps. Arcanine is another option, but I believe it would be more helpful for your crew in the long run.
Thanks for your help. That was really really helpful. I will give Krookodile a go as Sigilyph has already had HP - Fight and Samurott has Icy wind. But i will keep Cohagrigus. I love its role and annoyance. But I have never tried it before so maybe I will replace Cohagrigus with Roserade if it doesn't work for me. And I wonder, who should i teach Shadow Ball if I use Roserade?!
Anyway here is my Roserade and Krookodile. Please rate them if you like.
* Krookodile ( Moxie )
- Crunch
- Earthquake
- Outrage
- Strength
* Roserade ( Poison Point )
- Toxic Spikes
- Venoshock
- Giga drain
- Hidden Power - Rock