>>37872399Pokemon Reborn and (to a lesser extent) Pokemon Rejuvenation get a lot of flak for the "enemy gym leader gets a full OU team while you get shitmons" but in my experience this was only the case in maybe two gyms, both of which were unfortunately early on and probably caused a lot of ragequits.
Generally speaking, the Pokemon you catch early on in the wild are weak. Ekans, Grimer, Linoone, Pachirisu. With a bit of searching you can find some other mons that have a bit more oomph to them, like Goldeen (perfect counter to the electric gym), Espurr, Budew.
Of course, as the game goes on you get progressively stronger mons. They also limit access to popular mons, not specifically because they're strong but because they know players will naturally gravitate toward them because of familiarity alone. Some of my favourite parts of Reborn came from learning how strong Pokemon like Arbok and Fearow could be, because they learn strong moves and evolve early on. Then, when you get access to more Pokemon and can reach higher levels, you start to replace old Pokemon with new ones, start to mix and match different cores (Fire/Water/Grass turning into Fairy/Steel/Dragon, etc.), and especially trying to use Pokemon in the environment to your advantage in upcoming fights. Water gym is giving you trouble? Perfect opportunity to hunt down a Heliolisk or a Toxicroak, who you might not have considered otherwise.
Distribution is hard to pin down, because so much of it depends on what the game is throwing at you. Reborn always gave the player options, and they could approach a gym battle in several different ways no matter what point they were at.
If it's a gay Emerald romhack where the goal is to just give every Gym leader a full team of OU mons to sweep your shit, then giving the player powerful Pokemon early on serves more of a purpose. The biggest issue I have with bad distribution is when I catch a Pokemon early on and can safely say "This is probably never leaving my team".