Probably 3 good skills

[Pineapple]

A skill for the archer.
Coin stealer:
Increases the amount of coins collected from the monster by a certain percentage, has 5 levels, comes after the coin thief.
Skills for all classes in general.
Coin Snatcher:
Gives you more coins from the monster with a higher level, that is, if your level is higher this skill will be more useful, maybe 50-100 coins more at 100 level player.
Loot Snatcher:
Increases the chance loot to get loot, making it easier to get expensive sets, has 5 levels, and at max level could give a 25-100% bonus to a player's level 100."

[TheWood]

The general skills look useful.