I don't know about you guys but I would like to see new species of baddies introduced into Classic. The genre that the game is set in gives you all kinds of options for it this is one I came up with.
What I'm thinking of is some kind of Aviary type baddie as in Birds of the angry kind. Not ones that get shot from slingshots into pigs and bricks but some that are like vultures that would swoop down and attack you. They would probably be best suited to be placed in east Onnet and the lower to middle mountain areas and north west of York. Not only would they drop gralats,bombs,arrows,but they would also drop feathers that could be turned in some where for gralats/or pyrate bay type quest or to make some type of consumable item. You could even make a ginormous bird boss like the blob that gives you a big egg spoils with random rewards inside.
another option would be to introduce different species of small birds all over the map that you would be able to capture with your bug net that would work the same as catching bugs but with birds and you would turn them in or their feathers in for varying amounts of gralats depending on rarity. If I remember right you can do something similar to this on Skyword Sword
I don't think of few other new types of baddies would hurt either. It looks like Dusty is going to be placing some baddies in underground areas when and if the railroad system ever gets released. From the hints in pics he's used it seems like there are gonna be more of the soldier type baddies. I was thinking since they will be under ground they should be dwarves or Mole men. I just think it would be aestheticaly pleasing to have more of a variety of baddie instead of just 5.