Ultimate CF SL 7 Gearing Upgrade

Hi everyone,

First time climbing proper mountains and heading towards the Pyrenees in a couple of weeks.

Currently have the 2021 Canyon Ultimate CF SL 7 (https://99spokes.com/en-EU/bikes/canyon/2021/ultimate-cf-sl-7) with the original components, meaning a 54-36 chainring & 11-30T cassette combo. I'm pretty confident I will be begging for smaller gears when climbing for a long time, so I was looking to upgrade.

Current set-up:

• Rear derailleur: Shimano 105 R7000 SS, 11-speed, short cage design (max. cassette size: 30T)
• Cassette: Shimano 105 R7000 11-30T 11s
• Chain: Shimano HG601 11-speed

Was looking to "upgrade" to following:

• Rear derailleur: Shimano 105 RD R7000 GS 11-speed, medium cage
• Cassette: Shimano 105 CS-R7000 11 speed 11-34T
• Chain: keep
• Potentially, chainrings to 50-34

Is there anyone here who has experience doing the same, or has the knowledge to confirm?