I know they were thinking of changing the rules, but at least until recently you could not fly solo while training without a full PPL medical. So even if your intention was an RPL, you would still need a full PPL medical for at least part of your training.
I wasn’t aware of a 50nm distance requirement on an RPL. I semi-regularly fly further than this.
I am lucky in that I am a couple months away from 40 so the medical is easier for me and lasts for 5 years, however when I switch to 2 yearly medicals I may just go RPL. The only time I ever flown outside of my understanding of the RPL rules is when I have had more than one passenger. I basically keep a PPL for things such as IFR or night flying down the track. I have to get the driver’s license medicals anyway when I renew my class 5 driver’s licence (which I never use, but keep valid just on case).
In your situation I would probably look at getting a microlight license where you can train with the lower medical requirement. Many clubs now operate aircraft such as the Tecnam Sierra and they are very capable and cheaper to fly. Not sure where in Wellington you are but Wairarapa and Ruahine aero club in Masterton operate these I believe.
500ft