My Milestones are for now:
10 Downloads: NPC Reveal (REACHED!)
25 Downloads: New Rooms
40 Downloads: Boss Reveal
50 Downloads: Add Shop
65 Downloads: You Name an NPC
75 Downloads: Even more rooms
90 Downloads: Another 2 Bosses revealed
100 Downloads: You Name Another NPC & Release
After 100 the game will be considered as released and will be updated as a normal game rather as a demo.