Disagreeing with the first one since you can buy it, and if you are an ironman you chose to limit yourself. Maybe adding a bank closer to the flax fields would be a solution, or bowstrings/flax as something farmable or inside a drop table, who knows.
Agreeing with the second, forth and fifth suggestions. Rabbit foot is obtainable at 29 hunter, so why not make it a 35 crafting item? The tan-hide spell would be a faster but more costly way to tan hides, so why not, and a banker in the mining dungeon wouldn't be a bad addition since you have barbarian village ores with bank much closer, which makes people fight for the spots.
Now with the 3rd suggestion - no. They're not killed that often and the drops are rather useful and still kind of expensive. This would just crash the unique prices.