It's kind of bonkers at low level. It's more or less a switch for easy mode.
This statement strikes me as a bit hyperbolic. The feat is good...it does not turn tier one into a series of insignificant challenges, though.
Healing Kits are 5gp per kit, which is not an entirely insubstantial cost at low level.
The Trading Post on the Borderlands, is probably not going to have 10 in stock, ready to purchase.
So presuming the PC will always have a kit, (especially at low level), is not guaranteed.
Spending an action to bring an unconscious PC with 0 HP, to 1 HP, is a great way to prevent failed Death Saves due to 0 HP characters sustaining damage.
Yet at low level, I am more afraid of getting Instant Death from a critical hit, than getting a Coup de Grace when at 0 HP.
Being upright, at 1HP, (at levels 1-3), invites Instant Death. So this use of the Healers Kit at tier one almost needs a Healing Word chaser, which is a lot of resources to spend (HW spell + H Kit charge).
The short rest healing is very nice, especially in conjunction with other abilities like Song of Rest.
All these powers serve to do, is actually enable a group to get through an adventuring day, instead of the normal 5 minute 1st level workday.
My experience with 5e, is groups call for a short rest when HP are lower then desired. A long rest is called for when spell slots are depleted.
I don’t find the Healer Feat makes 6-8 encounters at levels 1-3 easier, it makes completing them
possible.