UPDATAN'.
Couple of notes:
1. I've cheated to get my Makuhita and Swablu early because most of my team doesn't appear before I get my 3rd badge... And I don't wanna be stuck with a Magikarp forever. The rest will be caught legitimately at their respective locations.
2. Keeping my starter until my entire party can train on it's own.
I started my Platinum Enhanced game. I like how I can get the Bicycle early in the game...
Anyway. I chose my starter, and it was Gible. I named her
Skulltag. Once it reached Level 7, it learned Dragon Ra
pge and started destroying everything. I got the Old Rod along with the Bicycle, and I fished myself a Magikarp. I named him
Crystal. And that's my official first member!
I leeched Crystal while Skulltag 1HKO'd everything. Then I reached Jubilife City. That means I got myself a Poketech... And then I battled my rival. Easy win.
Then, I caught myself a Swablu. I named her
Cloud 9. Going back to Route 204, I caught a Makuhita. I named him
Semper.
I trained Semper a lot, until like level 17. I took on Roark (who in this hack has 6 Pokemon, so does every other Gym Leader). It was a pretty easy sweep with Vital Throw. Got the first badge!
Moving on, I encoutered a huge problem: Mars. Her team consists of Pikachu, Umbreon and Raticate.
I had to grind, a lot. I evolved Semper into Hariyama and then took on Mars. Things were much easier. I leeched Crystal some more and it evolved into Gyarados, too.
I am currently in Eterna City, before doing any events. I'm considering mass grinding Cloud 9 as well, as it is very weak... And it's gonna take a while until it becomes an Altaria.
Current Party

Crystal : Level 24, Male, Hasty

Cloud 9 : Level 18, Female, Hasty

Semper : Level 26, Male, Impish

Skulltag : Level 14, Female, Hardy
To do list:
- Get Shuppet
- Get Bonsly / Sudowoodo
- Get Gulpin
- Evolve Swablu
- Beat Eterna Gym