Hi and welcome! I think you'll find plenty of information here that will guide you on your modding journey. I suspect your larger wing may be the mazda 6 option wing which wasn't officially part of the MPS body kit but could probably be requested as an option - The BK SP23 Mazda3 had a similar lip spoiler as standard and I ordered one years ago with the full wing. The RX-8 wheels are a good alternative fitment to the OEM wheels in terms of size....if you are interested I have some BK MPS3 wheels in Toowoomba QLD which are a match for the MPS6 OEM wheel fitment or if your looking for something more aggressive fitments up to 18x8.5 are doable. I'd suggest avoiding offsets below +45 but I am more familiar with the 3 myself. 18x8+50 through to 18x8+45 are definitely good fitments.
All the best - hope all the mechanical checks pass easily enough - rear diff mounts, engine mounts, timing chain and VVT actuator pop to mind as important to check out on recent purchase.
"Blue Meanie" 2007 Aurora Blue MPS 3 - 18x8.5+44 SSR GTX01 - 235/40R18 Michelin PS5 - 3.5" ETS TMIC - CPE stg 2 mount - HKS/CPE BPV - 2XS inlet - 2XS short shift - Corksport turbo manifold - HT 98 octane tune - Leather/Aluminium handbrake - Momo shifty knob - 7" touchscreen - JDM Mazda Retractable dashtop screen assembly - Bespoke Raspberry Pi Android based GPS/Carplay and instrumentation - 36AH reserve battery and C-TEK isolator - TEIN Street Advanced coilovers 1" drop - Superpro bushings - 220Kw/410Nm.
"Lipstick" 2013 Velocity Red MPS 3 - 18x7.5+48 Enkei RPF1 -225/40R18 Federal RS-RR - CPE TMIC - COBB inlet - CPE stg 2 mount - COBB Stage 1 98 octane tune - COBB shifty knob - 2XS short shift - 2XS turbo manifold.