I don't have anything new to bring to the table, indeed I'll be echoing some other posts, this just my 2c.
The early game progression being slower is a good idea, it's good for the low tier weapons to be useful for longer, but I find it just way TOO slow. As an experienced player I'm cranking up the xp multiplier to increase the gamestage, as the 'stone age' seems to take a ridiculously long time. However, if there was a slim chance of finding something good in safes I'd be happier. As it is, all early endeavours seem pointless (to me) bar hunting zombies for XP.
I'd even be happier if the early stage safes contain weapon parts, so it's not a quick 'win' condition, it still requires some luck, grind, and encourages trading between players. Or maybe limit the ammo drops, as I'm absolutely swimming in all ammo types by the time I get a firearm. I'd rather be able to find a gun and use it sparingly, than by the time I find one I'm instantly a one man army.
I understand the sentiment of enjoying the game world and taking things slow, building bases, but those things don't have to be at the detriment of the loot rooms.
On the whole, though, it's a great alpha. Especially traders in the towns, that simple change is awesome.