Grinding isnt really all the fun unless you are specifically going for a rare drop.
To get wings you need to get souls of flight, which requires you to kill 2-4 wyverns.
Honestly, Hardmode isnt all that tough once you get the gear you need. Make a helevator before hardmode, get some spelunker potions, and then make sure you break as many alters as you can. Then you take the helevator down with the spelunker potion activated and look for cobalt, then mithril, then adamantite, making a pickaxe from each tier. Once you get to adamantite, you make the armor from that tier.
Enemies aren't too tough either if you get the Clockwork assault rifle. Make sure you have max health and mana, aim for corruption for cursed bullets or hallow for crystal bullets.