1.Selling a SoulBound item should make the new boss drop new ones.
2.Get rid of Tapping or Change it to:
a.Gold ratio on loot and sell.
b.Increase of Stats.
3.You should be able to main a Character and have Him/Her a skill tree.
4.Class advancement:
Warrior>Knight(Tank)
Warrior>Paladin(Tank-Heal)
Healer>Priest(Heal-Buffer)
Healer>Witch(Heal-Debuffer)
Archer>Hunter(DPS-Attack Speed)
Archer>Sniper(DPS-Critical Damage)
Necro>Summoner(Summon Minions)
Necro>Wizard(DPS-AOE)
 "Idle Sword"){kind=icon}
 "Tap Adventure"){kind=icon}
I like the class advancement suggestion, but I'll leave that for the sequel! I might do a summon wand for the Necro though :)