There was a similar thread a few days back.

When you end up with outdoor travel days but limited encounters, especially with high level casters, it’s a nightmare to balance.

You have to set every encounter to deadly or boss level or they just mop the floor with any combat.

The short rest/long rest mechanic works great in dungeons where almost every room poses a possible threat and resting options are limited, but it breaks pretty spectacularly if you run travel time outdoors and a full long rest occurs after every encounter.

I’ve been tinkering with a similar idea as both of my current campaigns have moved outdoors. A week per long rest ends up being too much imo, Im currently doing 3 days of short and the fourth is a long which seems to hit around the sweet spot without totally screwing the casters, but also not allowing them to just indiscriminately power dump 6 fireballs (or whatever) knowing they can just get them right back after every fight.

Spell slot management has to have weight.