Mudkip is the best starter for the first 4 Gym Sweeping, with Water and Ground attacks.
Shromish/Breloom is good choice with Grass - Fighting moves, awesome speed and att.
Tailow/Swellow is good at speed, it can be a handful one.
Abra/Kadabra/Alakazam is a better choice than Ralts/Kirlia.
You gonna need a Dragon later, and I recommend Bagon. Although a little bit hard to get, but it's an awesome choice to beat the E4.
Finally, save a slot for Kyogre (you play Sapphire, right?). It's a very strong pkm.
Oh, and no, you don't have to waste your time on the stupid-weakling Surkit. It's just not worth it.