I just started a new game, choosing the name Amelia.
I'm in the Trick House doing the first puzzle, having just completed the Team Aqua event and delivered the goods.
As of right now my team consists of:
Marshtomp lvl 18 - I need to nickname it
William (Ralts) lvl 15
Chibi (Nincada) lvl 14 - this guy was a pain in the butt to level up.
Marco (Shroomish) lvl 15
Timmy (Taillow) lvl 15 - I'll probably get rid of this guy soon
Zigzagoon lvl 3 - my trusty HM slave with pickup :3
I don't know who else to add to my team though. I was thinking of perhaps getting a Magnemite and a fire type, but I'm not sure which - even though it should be an easy decision since there are only like 3 to choose from thanks to all the damn water.
Your team seems fine for the time being. I'd recommend replacing Taillow with Skarmory later (Route 113). And if you're looking for an electric type, Voltorb will work well (I'd say Magnemite, but if you have Skarmory on deck then you don't want another steel type). If you don't like Voltorb, evolve your Ralts into Gardevoir and teach it thunderbolt (thats what I'm using now, its a good substitute for an electric type and it frees up some space in your party). Later, I'd highly recommend replacing Shroomish/Breloom with Lileep/Cradily (Revived from root fossil found in the dessert above Mauville City). I used to use Breloom, but it outlives it's usefullness later on considering how it's Sp. Atk is not very high. It's just a fighting type with a 3 or 4 additional weaknesses, not to mention it's HIGHLY weak vs flying moves, whereas a fighting type like Medicham can take a hit from a flying type. I suppose halting evolution until it learns spore makes it semi useful, but when compared to Cradily, there is no competition in my opinion. As for fire types, I'd recommend Torkoal (Found in firery path) until you get to Mt. Pyre and can catch vulpix (I'd prefer Ninetales over Torkoal). Hope this helps.
I started my Sapphire over the other day, I just caught Kyogre. Now I'm spending time trying to improve my team, I don't think I can take on Wallace with where it is now:
Gardevior - Lv 38
Psychic
Thunderbolt
Calm Mind
Shadow Ball (I screwed up on this one... forgot it used Atk and not Sp. Atk)
Flygon - Lv 45
Crunch
Dragonbreath
Fly
Sand Tomb (Considering Earthquake, but it's female and couldn't pass the skill on)
Torchic - Lv 42
Slash
Ember (Will be replaced with Flamethrower next level, then I can evolve)
Quick Attack
Mirror Move
Lileep - Lv 24
Astonish
Constrict (Considering Giga Drain)
Acid (Considering Sludge Bomb)
Ingrain
Gyarados - Lv 26
This is only an hm slave, I'm not too fond of gyarados' Sp Atk.
I'm probably going to hunt feebas today, my team is in dire need of a Milotic. Other than that, the plan is to evolve my torchic and my lileep. I haven't decided who to add as my 6th pokemon. Salamence is overpopular, thus turning me away from it. We shall see...