Hi @EmmaBourke, I highly recommend that you heed the hard learnt lesson of @mfree, & follow in the footsteps of our beloved @Trying.
I believe that wood is beautiful, but I've learnt my lesson after making a stunning wooden deck, only to have it devoured by our very appreciative local termites. The positive, is that I didn't have to go through the drudgery of oiling, or staining it.
Visually, oiling wood darkens it, despite what salespersons may tell you. It also needs to be reapplied every 6 to 8 months, which borders on impossible. Not a problem mid-Summer, but try picking a day 6 to 8 months away, that won't have your new application washed away in the next 24 hours. I kept up the regime for years on our Western Red Cedar fence, but after a couple treatment being washed away with unexpected rains, I gave up in frustration. Our prized wooden structure, then weathered worse than Keith Richards, of the Rolling Stones.
The composite decking will definitely cost you more initially, but the long-term benefits over shadow it in terms of peace of mind, & convenience. If I had my time over again, I'd use composite materials, no doubt about it.
