After discussing with many people, I changed the percentage at which certain items drop from red boxes.
This is what I changed:
+1 now has a 100% chance drop
+2 now has a 60% chance drop
+3 now has a 20% chance drop
+4 now has a 5% chance drop
+5 now has a 1% chance drop
This means that +5 drops every 100 boxes or so, +4 drops every 20 boxes or so, +3 drops every 5 boxes or so, +2 drops every 2 boxes or so, and +1 drops if +2-+5 doesn't drop.
Before, it was this:
+1 had 100% chance drop
+2 had 60% chance drop
+3 had 45% chance drop
+4 had 20% chance drop
+5 had 5% chance drop
Discuss.