Good start to a guide. Here are some of the tips I have from my play experience so far:
- For Slotally Tober Saughter, you can still pick up beers that enemies drop in the level and get the achievement, you just can't use one of your beers in your inventory or die. I was able to unlock this achievement going back to the first level in hard mode (7-1) at level 42 and the best equipment I could find at the time with stats to increase all damage and bullet damage.
- If you still don't have Punch Many Bullets by the time you unlock hard mode, levels 8-1 (muddy village) and 8-3 (drilling grounds) are good stages to encounter a manageable amount of robots who shoot red bullets. I noticed I would kill 2 with 1 punch all the time with ease in these two levels.
- The best way to level up, in my experience, is to just keep pushing through the latest level you haven't beaten. Previous levels (even survival levels) stop giving decent experience pretty quickly after you beat them, so it's best to play the hardest level you haven't beaten, even if you die a lot as experience doesn't reset upon death. You DO need to beat the level in order for the experience you've gained to save, so you might be in for a long haul if you are heavily outgunned in a particular level.