My list for quality of life upgrades on a Volkswagen Mk6.
A lot of these are also applicable to the MK5, though you should verify parts interchangeability before purchase for a MK5.
VCDS vs OBD11 from Humble Mechanic
https://youtu.be/Sc9NxLrL_Rw
POV driving footage from my boy -
https://youtube.com/@vanillastudios1562?si=KdslxEmPEB37hTFv
Links for items available - Not linking eBay items since the links eventually die out.
Interior LED lights - https://amzn.to/3Rh9xUg
Interior trim tool kit - https://amzn.to/3Gkb3yI
Skoda washer fluid cap - https://amzn.to/47nPPMd
Automatic headlight switch - https://amzn.to/3BHPmtx
LED Reverse Bulbs - https://www.uspmotorsports.com/product/rfb-t20-led-canbus-pair-75005681
VW Roadside kits - https://amzn.to/40VWWsJ
Blue, aspherical side mirrors - https://amzn.to/3uFmXQW
Cargo cover - https://amzn.to/47RAl2V
OBD11 - https://amzn.to/47Oze3Y
VCDS - https://store.ross-tech.com/shop/cat/VCDS/
RCD330 - https://amzn.to/3N1k17U
Wireless charger ashtray - https://amzn.to/3tnB11u
Under seat storage tray- https://www.ecstuning.com/b-genuine-volkswagen-audi-parts/drivers-seat-tray-kit-titanium-black/1ko898036/