As a former playtester for salt2, these are generally some changes I would have loved in the final release (maybe not all this extreme).

(Last updated for 1.3.1)

Armor

All armor grants 20% more defense.

Blocking
Block and perfect block now stay active from a single tap. (No longer requires button holding).
Block stamina cost is now reduced on a sliding scale where low values are unchanged and high values are reduced by 20%.
Perfect block stamina cost is removed completely.
Perfect block on a couple weapons buffed by 1 frame (1/60) just for fun or ease of use.
Block animation no longer cancels when released. Forced minimum block timer.
Perfect block cooldown reduced/removed to match animation changes.
Block animation stun/lock reduced slightly.
Block animation stun/lock can now be escaped with light attack.
Perfect block window is extended when successful for 2 frames to protect from fast enemies you can't react to.

Charms

Health on perfect block Charm buffed from 2.5% max HP over 5 seconds to 5% over 1 second.
Focus on perfect block Charm buffed from 2.5% max FP over 5 seconds to 5% over 1 second.

Weight

Players now start with +8 carry max.

Random Salt1 Stuff

Great hammers are 90% larger and their reach has been adjusted to match their texture. (Similar to Salt1)
Extreme hair colors added. (Like salt1, same color codes)

Dedicated Saves

Version 1.2 onward now copies any saves you have to a new folder and uses that folder for future saves.