Pokemon D/P/PT GBA (help wanted)

I want to try to make a demake of Diamond, Pearl, and / or Platinum in Gen 3, I am pretty new to hacking so I'd like to use this as a learning experience.
Here are some things that I'd like to add to this hack:
- FireRed or Emerald Engine (I'm not sure which would be better for this)
- Gen 4 trainer sprites
- Gen 4 soundtrack devamps
- Gen 4 Pokemon w/ respective sprites
- Gen 4+ Movepools
- Gen 4 events and mechanics like putting honey on trees for combee
- Pokemon Encounter places similar to Diamond, Pearl, or Platinum (Maybe all mons obtainable)
- Tileset similar to Gen 4
- Possibly mega evolution

I know it may seem a bit ambitious because I know we can't make it exactly the game since it isn't made for the same hardware and the GBA might have limitations that the

I have some ripped D/P/P music and SFX on my PC but I don't know where they're from. I can send those to you.

Also, there may be some sprites available on Spriters Resource, information on Pokemon stats in Gen4 can generally be found on https://pokemondb.net/pokedex/stats/gen4

And a quick suggestion, you may want to make 3 versions to catch them on different versions, mainly for traditional purposes.

You can use PGE to add moves (and expand rom size)

Extra resources:
https://www.pokecommunity.com/showthread.php?t=234550
https://www.pokecommunity.com/showthread.php?t=364889