I've played quite a bit of MA, and I think needs some changes. First and foremost, remove the Axeman class. In terms of DPS(by calculating the attack speed and attack damage), the Sword does more overall damage, meaning that the Axeman is useless compared to the Swordsman. Second: Replace Axeman with some type of potion-user. Alchemist/Brewer or something. Starts out with infinite splash potions of poison, and at higher levels gets access to limited amounts of splash regen potions, splash instant heal potions, and splash instant damage potions. The strength of the potions can also increase as the player's level goes up. Has the ability to purchase potions for emeralds(maybe a stack of each for 30 emeralds). This class will be useful in solo play and in a team scenario because he can function as a healer for the team as well as providing a medium amount of instant and poison damage to large groups. Third: Allow us to purchase Iron armor with emeralds. Often I find games where I'm playing solo and have 2+ stacks of emeralds and nothing to spend it on because I already have a diamond sword, a bow, and a crap ton of arrows and steak. It would make sense for us to purchase Iron armor, because it makes sense seeing as we can purchase Iron swords. Fourth: Make some of the rounds more solid when it comes to monster spawns. Wave 1 should be 2 zombies and a small chance of 1 zombie 1 skeleton. Waves 2-10 should be minimum one skeleton and the rest zombies with a small chance of one of the zombies being a pigman or a baby zombie. Waves 11-20 should be at least 2 to 3 skeletons, 1-2 spiders and the rest either zombies, pigmen, or baby zombies. Waves 21-30 should be at least 3 skeletons, 2 spiders and the rest zombies, baby zombies, pigmen, or baby pigmen. Waves 31 and beyond should be at least 5 skeletons, 4 spiders, and 3 creepers, with the rest of the wave being zombies, baby zombies, pigmen, or baby pigmen. The fourth change isn't really needed; all it'll do is make the waves a bit harder to manage once the game lengthens, meaning that you need a team with a tank and an archer once it hits wave 31 and up. EDIT: Changed the 2nd paragraph to reflect correct information. EDIT 2: Changed 2nd paragraph again to reflect correct information(I got it right this time xd)
