would expect the leather to get more than 20-50 due to it being perfect and people like complete sets, however to find that type of buyer might take a bit longer and still would be between 100-300
yes that charm is like 40 these days, new players are generally funneled to make melee classes as they're easier to do, so there's no demand for weak charms.
map is insane, should be 1k+, deserves its own topic and might as well throw a red/bold on it, the 10 fg you'll easily get back
for whites, can try higher than what i've got on my list, if it sells let me know and i'll modify the list.
for the charm, it fully depends on how much strength you're using. in general if you have around 100 strength, 1 crit is around 1.5-2 strength. if you have 200 strength, 1 crit is then worth around 2.5. at 300 strength, 1 crit is worth around 3 strength.
so for solo purposes, the ice counts as around 32-34 strength, although seeing it's usable 10 levels earlier than the fire, i'd generally use that.
you can mess around with the damage calculator to test a few builds, although axes/charms havent had testing done for crit so no values exist for those:
https://docs.google.com/spreadsheets/d/1RDkoYfhQSyWW0KNRYTAWZRLxVfeYGgj-nwqOwtgtSOs/edit?gid=0#gid=0